mesa-users — open list for mesa comments, questions, & answers

Re: [mesa-users] Proper use of eosDE

[Bill P. <pa...@ki...>]

Hi Phil,

Great to hear from you.  I was recently wondering what you were up to these days.

Your questions are an excellent synopsis of why I dislike using density and energy as primary EOS variables in an evolution code.
Given my bias against it, you'll probably get better advice from someone else, for example someone who uses HELM for their hydro code.
The best way to avoid the problems you mention is to use density and temperature as your basic variables so you are in harmony with the input physics.
I can do that with my implicit hydro, including the new version using approximate Riemann HLLC, but it may not be possible for you.  Life is hard.

Good luck - I'm sure you'll find a way to make it work.

Bill




On Jul 22, 2017, at 11:04 PM, Philip Chang wrote:

> Hi,
> 
> I'm integrating the mesa eos module into a hydro code that I am writing/written.  I have lots of experience with Frank Timmes Helmholtz eos (which I got from his website), but for my new code I am going to use the MESA eos.  Anyhow, my hydro code gives me an internal energy and density and I want to get other thermal quantities, i.e., temperature, entropy, adiabatic index, etc.
> 
> The way to do this is using eosDE_get, but I'm not sure what the proper use of this was and was hoping that someone knew offhand. I am using the latest public release 9793.  In particular, my questions are:
> 
> 1. How does one decide on a proper T_guess?  I looked in the mesa-star code, and it appears that one want to use the temperature from the previous step.  I'm wondering how good is this as a shock can move though a cell and totally mess everything up.
> 
> 2. An improper T_guess can usually be corrected, i.e., it produced values that are obviously wrong.  I have tried a guess of 1e2 and 1e8 and usually if one fails then the other gives you a good value. But this is not always the case, for instance, consider this particular pathological case: rho = 794.32840915212967, T=158489.31924611141, solar metallicity.
> 
> For T_guess = 1e7, I find T = 202665.40667059086
> 
> For T_guess = 1e2, I find T = 257198.81215480756
> 
> In this case both are wrong by order unity.  This is a particular bad case as both guess give poor answers.  But there are cases where one guess give a good answer, but the other does not, and it is not obvious which one I should trust.  Any ideas?
> 
> 3. What happens when the internal energy is too low?  For instance, in my previous experience with the Helmholtz equation of state (from Frank Timmes website), small fluctuations can drop the internal energy below the fermi energy.  When this energy is use to try to find a temperature in the Helmholtz equation of state, the code essentially crashed (as it should).  In this case, I prechecked the internal energy to ensure that it is valid.  What happens if I give the eosDE_get an internal energy that is physically too small.
> 
> Thanks in advance for any help.
> 
> Cheers,
> 
> Phil Chang
> 
> 
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> _______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users

[mesa-users] Proper use of eosDE

[Philip C. <ch...@uw...>]

Hi,

I'm integrating the mesa eos module into a hydro code that I am 
writing/written.  I have lots of experience with Frank Timmes Helmholtz 
eos (which I got from his website), but for my new code I am going to 
use the MESA eos.  Anyhow, my hydro code gives me an internal energy and 
density and I want to get other thermal quantities, i.e., temperature, 
entropy, adiabatic index, etc.

The way to do this is using eosDE_get, but I'm not sure what the proper 
use of this was and was hoping that someone knew offhand. I am using the 
latest public release 9793.  In particular, my questions are:

1. How does one decide on a proper T_guess?  I looked in the mesa-star 
code, and it appears that one want to use the temperature from the 
previous step.  I'm wondering how good is this as a shock can move 
though a cell and totally mess everything up.

2. An improper T_guess can usually be corrected, i.e., it produced 
values that are obviously wrong.  I have tried a guess of 1e2 and 1e8 
and usually if one fails then the other gives you a good value. But this 
is not always the case, for instance, consider this particular 
pathological case: rho = 794.32840915212967, T=158489.31924611141, solar 
metallicity.

For T_guess = 1e7, I find T = 202665.40667059086

For T_guess = 1e2, I find T = 257198.81215480756

In this case both are wrong by order unity.  This is a particular bad 
case as both guess give poor answers.  But there are cases where one 
guess give a good answer, but the other does not, and it is not obvious 
which one I should trust.  Any ideas?

3. What happens when the internal energy is too low?  For instance, in 
my previous experience with the Helmholtz equation of state (from Frank 
Timmes website), small fluctuations can drop the internal energy below 
the fermi energy.  When this energy is use to try to find a temperature 
in the Helmholtz equation of state, the code essentially crashed (as it 
should).  In this case, I prechecked the internal energy to ensure that 
it is valid.  What happens if I give the eosDE_get an internal energy 
that is physically too small.

Thanks in advance for any help.

Cheers,

Phil Chang

Re: [mesa-users] MESA__overshooting__overshoot_alpha

[Frank T. <fx...@ma...>]

as for the physical meaning of the parameter,
you may want to consult a stellar evolution textbook,
for example, hansen and kawaler's "stellar interiors" 
followed by a reading of the mesa instrument papers 
given on http://mesa.sourceforge.net/prereqs.html .

fxt





> On Jul 21, 2017, at 7:06 PM, 贺祥 <he...@yn...> wrote:
> 
> Hi Pablo Marchant.
> 
> Sorry, it should be " overshoot_alpha".
> 
> Best wishes,
> 
> Xiang He
> 
> -----原始邮件-----
> 发件人: "Pablo Marchant" <pa...@gm...>
> 发送时间: 2017年7月22日 星期六
> 收件人: "贺祥" <he...@yn...>
> 抄送: "mes...@li..." <mes...@li...>
> 主题: Re: [mesa-users] MESA__overshooting__overshoot_alpha
> 
> 
> Hi Xiang,
> 
> what do you mean with that? MESA has no parameter called overshooting_overshoot_alpha. If you're trying to set overshoot, then check the options available here:
> 
> http://mesa.sourceforge.net/controls_defaults.html#overshooting
> 
> Cheers
> 
> On Fri, Jul 21, 2017 at 6:36 AM, 贺祥 <he...@yn...> wrote:
> Hi all,
> 
> I am a new user of MESA code. Recently, I  was  confused  with the parameter "overshooting_overshoot_alpha".  I don't fully understand the meaning of this parameter and what kind of value should I take for this paramter.  Is there any one who can explain to me? Thanks in advanced.
> 
> Best wishes,
> 
> Xiang He
> 
> 
> 
> 
> 
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> _______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users
> 
> 
> 
> 
> -- 
> Pablo Marchant Campos
> M.Sc on Astrophysics, Universidad Católica de Chile
> PhD on Astrophysics, Argelander-Institut für Astronomie, Universität Bonn
> 
> 
> 
> 
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot_______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users

Re: [mesa-users] MESA__overshooting__overshoot_alpha

[贺祥 <he...@yn...>]

Hi Pablo Marchant.

Sorry, it should be " overshoot_alpha".

Best wishes,

Xiang He

-----原始邮件-----
发件人: "Pablo Marchant" <pa...@gm...>
发送时间: 2017年7月22日 星期六
收件人: "贺祥" <he...@yn...>
抄送: "mes...@li..." <mes...@li...>
主题: Re: [mesa-users] MESA__overshooting__overshoot_alpha



Hi Xiang,


what do you mean with that? MESA has no parameter called overshooting_overshoot_alpha. If you're trying to set overshoot, then check the options available here:


http://mesa.sourceforge.net/controls_defaults.html#overshooting



Cheers


On Fri, Jul 21, 2017 at 6:36 AM, 贺祥 <he...@yn...> wrote:


Hi all,

I am a new user of MESA code. Recently, I  was  confused  with the parameter "overshooting_overshoot_alpha".  I don't fully understand the meaning of this parameter and what kind of value should I take for this paramter.  Is there any one who can explain to me? Thanks in advanced.

Best wishes,

Xiang He





------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
mesa-users mailing list
mes...@li...
https://lists.sourceforge.net/lists/listinfo/mesa-users







--

Pablo Marchant Campos
M.Sc on Astrophysics, Universidad Católica de Chile
PhD on Astrophysics, Argelander-Institut für Astronomie, Universität Bonn

Re: [mesa-users] MESA__overshooting__overshoot_alpha

[Pablo M. <pa...@gm...>]

Hi Xiang,

what do you mean with that? MESA has no parameter
called overshooting_overshoot_alpha. If you're trying to set overshoot,
then check the options available here:

http://mesa.sourceforge.net/controls_defaults.html#overshooting

Cheers

On Fri, Jul 21, 2017 at 6:36 AM, 贺祥 <he...@yn...> wrote:

> Hi all,
>
> I am a new user of MESA code. Recently, I  was  confused  with the
> parameter "overshooting_overshoot_alpha".  I don't fully understand the
> meaning of this parameter and what kind of value should I take for this
> paramter.  Is there any one who can explain to me? Thanks in advanced.
>
> Best wishes,
>
> Xiang He
>
>
>
>
> ------------------------------------------------------------
> ------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> _______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users
>
>


-- 
Pablo Marchant Campos
M.Sc on Astrophysics, Universidad Católica de Chile
PhD on Astrophysics, Argelander-Institut für Astronomie, Universität Bonn

[mesa-users] MESA__overshooting__overshoot_alpha

[贺祥 <he...@yn...>]

Hi all,

I am a new user of MESA code. Recently, I  was  confused  with the parameter "overshooting_overshoot_alpha".  I don't fully understand the meaning of this parameter and what kind of value should I take for this paramter.  Is there any one who can explain to me? Thanks in advanced.

Best wishes,

Xiang He

Re: [mesa-users] Inlist issue

[Yevgeni K. <jen...@gm...>]

Hi Frank,

Thank you for responding.

Is it rotation that triggers an issue with the ZAMS flag?

I set up accretion on a pre-MS 3M_o core. I then choose the model closest
in mass to what I
am after and restart from the corresponding photo. I used this setup
numerous times before,
but this is the first time I attempt to include rotation.

I figured I don't want to include rotation in the pre-MS model, since I am
looking for a certain rate
on the ZAMS (which is shortly after the first model I restart from - the
model relaxes quickly).

Thank you,

Yevgeni.

On 20 July 2017 at 15:02, Frank Timmes <fx...@ma...> wrote:

> inlist_massive_star creates a pre-main sequence model
>
>       create_pre_main_sequence_model = .true.
>
> rather than load a previous model. in such cases it can be useful
> to turn on rotation when the pre-ms model is near zams. for example,
>
>       new_rotation_flag = .true.
>       change_rotation_flag = .false.                 ! rotation off until
> near zams
>       near_zams_relax_omega_div_omega_crit = .true.  ! true to turn on
> rotation at zams
>       num_steps_to_relax_rotation = 100              ! use this many steps
> in relaxing
>       new_omega_div_omega_crit = 0.10d0
>
> explore http://mesa.sourceforge.net/star_job_defaults.html#
> rotation_controls
> to find the relevant controls for omega instead of the omega_div_omega_crit
> used in the above example.
>
> fxt
>
>
>
>
> > On Jul 20, 2017, at 10:26 AM, Yevgeni Kissin <jen...@gm...>
> wrote:
> >
> > Hi everyone,
> >
> > I am attempting to modify an inlist that has worked for me numerous
> times, by adding controls for
> > rotation and resulting mixing. Once I do so, all the controls below the
> mixing values fail to be
> > registered (i.e. their values revert to defaults).
> >
> > I am including the inlist here, and I enclosed the new values in '!!!!'
> (should be evident).
> >
> > I tried moving the new values to the bottom of the inlist, but when I
> run I get a series of messages:
> > " s% omega(k)        ###     NaN "
> > which I believe is due to me setting a rotation rate, without activating
> mixing (hence the control
> > command does not get recognized).
> >
> > Is there a limit to the length of the inlist, or what could be the issue
> here?
> >
> > I will point out that this inlist is used to restart from an image of a
> 3M_o pre-MS model which experienced
> > accretion up to 13M_o (hence it's a 13M_o ZAMS model).
> >
> > Thank you very much.
> >
> > Yevgeni.
> > <inlist_massive_star>---------------------------------------
> ---------------------------------------
> > Check out the vibrant tech community on one of the world's most
> > engaging tech sites, Slashdot.org! http://sdm.link/slashdot______
> _________________________________________
> > mesa-users mailing list
> > mes...@li...
> > https://lists.sourceforge.net/lists/listinfo/mesa-users
>
>

Re: [mesa-users] Inlist issue

[Frank T. <fx...@ma...>]

inlist_massive_star creates a pre-main sequence model

      create_pre_main_sequence_model = .true.

rather than load a previous model. in such cases it can be useful
to turn on rotation when the pre-ms model is near zams. for example,

      new_rotation_flag = .true.
      change_rotation_flag = .false.                 ! rotation off until near zams
      near_zams_relax_omega_div_omega_crit = .true.  ! true to turn on rotation at zams
      num_steps_to_relax_rotation = 100              ! use this many steps in relaxing
      new_omega_div_omega_crit = 0.10d0

explore http://mesa.sourceforge.net/star_job_defaults.html#rotation_controls
to find the relevant controls for omega instead of the omega_div_omega_crit 
used in the above example.

fxt




> On Jul 20, 2017, at 10:26 AM, Yevgeni Kissin <jen...@gm...> wrote:
> 
> Hi everyone,
> 
> I am attempting to modify an inlist that has worked for me numerous times, by adding controls for
> rotation and resulting mixing. Once I do so, all the controls below the mixing values fail to be 
> registered (i.e. their values revert to defaults).
> 
> I am including the inlist here, and I enclosed the new values in '!!!!' (should be evident).
> 
> I tried moving the new values to the bottom of the inlist, but when I run I get a series of messages:
> " s% omega(k)        ###     NaN "
> which I believe is due to me setting a rotation rate, without activating mixing (hence the control
> command does not get recognized).
> 
> Is there a limit to the length of the inlist, or what could be the issue here?
> 
> I will point out that this inlist is used to restart from an image of a 3M_o pre-MS model which experienced
> accretion up to 13M_o (hence it's a 13M_o ZAMS model).
> 
> Thank you very much.
> 
> Yevgeni.
> <inlist_massive_star>------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot_______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users

[mesa-users] Inlist issue

[Yevgeni K. <jen...@gm...>]

Hi everyone,

I am attempting to modify an inlist that has worked for me numerous times,
by adding controls for
rotation and resulting mixing. Once I do so, all the controls below the
mixing values fail to be
registered (i.e. their values revert to defaults).

I am including the inlist here, and I enclosed the new values in '!!!!'
(should be evident).

I tried moving the new values to the bottom of the inlist, but when I run I
get a series of messages:
" s% omega(k)        ###     NaN "
which I believe is due to me setting a rotation rate, without activating
mixing (hence the control
command does not get recognized).

Is there a limit to the length of the inlist, or what could be the issue
here?

I will point out that this inlist is used to restart from an image of a
3M_o pre-MS model which experienced
accretion up to 13M_o (hence it's a 13M_o ZAMS model).

Thank you very much.

Yevgeni.

Re: [mesa-users] Overflowing initial model for binary systems

[Talha I. <tlh...@gm...>]

I don't think I ever looked into that option. That seems to have fixed it.

Thank you so much!

Best,
Talha

Talha Irfan Khawaja
Physics '19
Georgia Institute of Technology

On 18 July 2017 at 19:30, Pablo Marchant <pa...@gm...> wrote:

> Apparently, you are using the default inlist_zams_specification which only
> produces a model for a single mass, 20 Msun. This is set by the options
>
>     mlo = 1.30102999566398d0
>     mhi = 1.30102999566398d0
>     dmass = 0.6d0
>
> in that inlist, where mlo and mhi are the logarithm of the masses to be
> included in the ZAMS file, and dmass is the logarithmic interval between
> models. So your binary model runs into problems trying to initiate with
> different initial masses, because the ZAMS file only provides one mass.
> Actually, if I switch in your inlist project m1=20 and m2=20, it works
> without problems.
>
> The reason the default in the test_suite has those values is just because
> its a test, what you really want is to sample multiple masses to create
> your ZAMS models. This is something you only have to do once for a choice
> of composition, then you can reuse the saved models permanently by putting
> it in $MESA_DIR/data/star_data/zams_models/.
>
> In particular for some of my models I do
>
>    ! do masses 10**lgm, for lgm = mlo to mhi by dmass
>    mlo = 0
>    mhi = 2
>    dmass = 0.02d0
>
> This will take a while, as it has to compute 100 stellar models, but as I
> said, this is a thing you do only a very limited amount of times.
>
> Cheers
>
> On Tue, Jul 18, 2017 at 4:22 PM, Talha Irfan <tlh...@gm...> wrote:
>
>> I've attached a couple of the more recent models I've been using. The
>> file 'z1d_2.data' is the most recent, and the one which I was testing with
>> the inlists from earlier.
>>
>> Best,
>> Talha
>>
>> Talha Irfan Khawaja
>> Physics '19
>> Georgia Institute of Technology
>>
>> On 18 July 2017 at 15:56, Pablo Marchant <pa...@gm...> wrote:
>>
>>> Hi Talha,
>>>
>>> can you provide your zams models as well to avoid having to recompute
>>> them?
>>>
>>> On Jul 18, 2017 1:57 PM, "Talha Irfan" <tal...@ga...> wrote:
>>>
>>>> Hi everyone,
>>>>
>>>> I've been using MESA to investigate population II and III stars by
>>>> controlling this intial_z value for singular stars. This was working fine
>>>> until I moved to the binary case, where I used the second set of
>>>> instructions from this
>>>> <https://sourceforge.net/p/mesa/mailman/message/34896105/> post to
>>>> create my own ZAMS model with certain initial_z values, then matching that
>>>> in the inlists from the binary work folder.
>>>>
>>>> I've been having problems trying to evolve the system, even if I set
>>>> evolve_both_stars to false (after initially trying true). The first
>>>> termination code read "Terminate because of overflowing initial model", so
>>>> I tried increasing the initial period as some users had suggested, and
>>>> later tried setting ignore_rlof to true, both of which resulted in failure
>>>> to find a suitable model. I'm not really sure where to go from here, so
>>>> I've attached my inlists (the only ones I edited) and the
>>>> inlist_zams_specification I used. I'd greatly appreciate any help with this.
>>>>
>>>> Thanks!
>>>>
>>>>
>>>> Talha Irfan Khawaja
>>>> Physics '19
>>>> Georgia Institute of Technology
>>>>
>>>>
>>>> ------------------------------------------------------------
>>>> ------------------
>>>> Check out the vibrant tech community on one of the world's most
>>>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>>>> _______________________________________________
>>>> mesa-users mailing list
>>>> mes...@li...
>>>> https://lists.sourceforge.net/lists/listinfo/mesa-users
>>>>
>>>>
>>
>
>
> --
> Pablo Marchant Campos
> M.Sc on Astrophysics, Universidad Católica de Chile
> PhD on Astrophysics, Argelander-Institut für Astronomie, Universität Bonn
>

Re: [mesa-users] Overflowing initial model for binary systems

[Pablo M. <pa...@gm...>]

Apparently, you are using the default inlist_zams_specification which only
produces a model for a single mass, 20 Msun. This is set by the options

    mlo = 1.30102999566398d0
    mhi = 1.30102999566398d0
    dmass = 0.6d0

in that inlist, where mlo and mhi are the logarithm of the masses to be
included in the ZAMS file, and dmass is the logarithmic interval between
models. So your binary model runs into problems trying to initiate with
different initial masses, because the ZAMS file only provides one mass.
Actually, if I switch in your inlist project m1=20 and m2=20, it works
without problems.

The reason the default in the test_suite has those values is just because
its a test, what you really want is to sample multiple masses to create
your ZAMS models. This is something you only have to do once for a choice
of composition, then you can reuse the saved models permanently by putting
it in $MESA_DIR/data/star_data/zams_models/.

In particular for some of my models I do

   ! do masses 10**lgm, for lgm = mlo to mhi by dmass
   mlo = 0
   mhi = 2
   dmass = 0.02d0

This will take a while, as it has to compute 100 stellar models, but as I
said, this is a thing you do only a very limited amount of times.

Cheers

On Tue, Jul 18, 2017 at 4:22 PM, Talha Irfan <tlh...@gm...> wrote:

> I've attached a couple of the more recent models I've been using. The file
> 'z1d_2.data' is the most recent, and the one which I was testing with the
> inlists from earlier.
>
> Best,
> Talha
>
> Talha Irfan Khawaja
> Physics '19
> Georgia Institute of Technology
>
> On 18 July 2017 at 15:56, Pablo Marchant <pa...@gm...> wrote:
>
>> Hi Talha,
>>
>> can you provide your zams models as well to avoid having to recompute
>> them?
>>
>> On Jul 18, 2017 1:57 PM, "Talha Irfan" <tal...@ga...> wrote:
>>
>>> Hi everyone,
>>>
>>> I've been using MESA to investigate population II and III stars by
>>> controlling this intial_z value for singular stars. This was working fine
>>> until I moved to the binary case, where I used the second set of
>>> instructions from this
>>> <https://sourceforge.net/p/mesa/mailman/message/34896105/> post to
>>> create my own ZAMS model with certain initial_z values, then matching that
>>> in the inlists from the binary work folder.
>>>
>>> I've been having problems trying to evolve the system, even if I set
>>> evolve_both_stars to false (after initially trying true). The first
>>> termination code read "Terminate because of overflowing initial model", so
>>> I tried increasing the initial period as some users had suggested, and
>>> later tried setting ignore_rlof to true, both of which resulted in failure
>>> to find a suitable model. I'm not really sure where to go from here, so
>>> I've attached my inlists (the only ones I edited) and the
>>> inlist_zams_specification I used. I'd greatly appreciate any help with this.
>>>
>>> Thanks!
>>>
>>>
>>> Talha Irfan Khawaja
>>> Physics '19
>>> Georgia Institute of Technology
>>>
>>>
>>> ------------------------------------------------------------
>>> ------------------
>>> Check out the vibrant tech community on one of the world's most
>>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>>> _______________________________________________
>>> mesa-users mailing list
>>> mes...@li...
>>> https://lists.sourceforge.net/lists/listinfo/mesa-users
>>>
>>>
>


-- 
Pablo Marchant Campos
M.Sc on Astrophysics, Universidad Católica de Chile
PhD on Astrophysics, Argelander-Institut für Astronomie, Universität Bonn

Re: [mesa-users] Overflowing initial model for binary systems

[Talha I. <tlh...@gm...>]

I've attached a couple of the more recent models I've been using. The file
'z1d_2.data' is the most recent, and the one which I was testing with the
inlists from earlier.

Best,
Talha

Talha Irfan Khawaja
Physics '19
Georgia Institute of Technology

On 18 July 2017 at 15:56, Pablo Marchant <pa...@gm...> wrote:

> Hi Talha,
>
> can you provide your zams models as well to avoid having to recompute them?
>
> On Jul 18, 2017 1:57 PM, "Talha Irfan" <tal...@ga...> wrote:
>
>> Hi everyone,
>>
>> I've been using MESA to investigate population II and III stars by
>> controlling this intial_z value for singular stars. This was working fine
>> until I moved to the binary case, where I used the second set of
>> instructions from this
>> <https://sourceforge.net/p/mesa/mailman/message/34896105/> post to
>> create my own ZAMS model with certain initial_z values, then matching that
>> in the inlists from the binary work folder.
>>
>> I've been having problems trying to evolve the system, even if I set
>> evolve_both_stars to false (after initially trying true). The first
>> termination code read "Terminate because of overflowing initial model", so
>> I tried increasing the initial period as some users had suggested, and
>> later tried setting ignore_rlof to true, both of which resulted in failure
>> to find a suitable model. I'm not really sure where to go from here, so
>> I've attached my inlists (the only ones I edited) and the
>> inlist_zams_specification I used. I'd greatly appreciate any help with this.
>>
>> Thanks!
>>
>>
>> Talha Irfan Khawaja
>> Physics '19
>> Georgia Institute of Technology
>>
>>
>> ------------------------------------------------------------
>> ------------------
>> Check out the vibrant tech community on one of the world's most
>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>> _______________________________________________
>> mesa-users mailing list
>> mes...@li...
>> https://lists.sourceforge.net/lists/listinfo/mesa-users
>>
>>

Re: [mesa-users] Overflowing initial model for binary systems

[Pablo M. <pa...@gm...>]

Hi Talha,

can you provide your zams models as well to avoid having to recompute them?

On Jul 18, 2017 1:57 PM, "Talha Irfan" <tal...@ga...> wrote:

> Hi everyone,
>
> I've been using MESA to investigate population II and III stars by
> controlling this intial_z value for singular stars. This was working fine
> until I moved to the binary case, where I used the second set of
> instructions from this
> <https://sourceforge.net/p/mesa/mailman/message/34896105/> post to create
> my own ZAMS model with certain initial_z values, then matching that in the
> inlists from the binary work folder.
>
> I've been having problems trying to evolve the system, even if I set
> evolve_both_stars to false (after initially trying true). The first
> termination code read "Terminate because of overflowing initial model", so
> I tried increasing the initial period as some users had suggested, and
> later tried setting ignore_rlof to true, both of which resulted in failure
> to find a suitable model. I'm not really sure where to go from here, so
> I've attached my inlists (the only ones I edited) and the
> inlist_zams_specification I used. I'd greatly appreciate any help with this.
>
> Thanks!
>
>
> Talha Irfan Khawaja
> Physics '19
> Georgia Institute of Technology
>
>
> ------------------------------------------------------------
> ------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> _______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users
>
>

[mesa-users] Overflowing initial model for binary systems

[Talha I. <tal...@ga...>]

Hi everyone,

I've been using MESA to investigate population II and III stars by
controlling this intial_z value for singular stars. This was working fine
until I moved to the binary case, where I used the second set of
instructions from this
<https://sourceforge.net/p/mesa/mailman/message/34896105/> post to create
my own ZAMS model with certain initial_z values, then matching that in the
inlists from the binary work folder.

I've been having problems trying to evolve the system, even if I set
evolve_both_stars to false (after initially trying true). The first
termination code read "Terminate because of overflowing initial model", so
I tried increasing the initial period as some users had suggested, and
later tried setting ignore_rlof to true, both of which resulted in failure
to find a suitable model. I'm not really sure where to go from here, so
I've attached my inlists (the only ones I edited) and the
inlist_zams_specification I used. I'd greatly appreciate any help with this.

Thanks!


Talha Irfan Khawaja
Physics '19
Georgia Institute of Technology

Re: [mesa-users] Setting up MESA on Amazon EC2 Instances

[Frank T. <fx...@ma...>]

hi andrew,

thanks for your excellent and detailed guide on how
to get mesa running on ec2!

fxt



> On Jul 18, 2017, at 7:55 AM, Andrew Mizener <ami...@ma...> wrote:
> 
> Hello!
> 
> I’m a summer undergraduate researcher. As part of my project, I set up MESA on multiple Amazon EC2 instances. This is a service that allows users to rent remote virtual computers. By using this, I was able to get many more runs with MESA completed than I would have otherwise. My advisor tells me that it would be helpful if I shared my knowledge about this with the MESA community. So, I’ve typed up a guide that explains how one can set up and use MESA with this service. I’ve tried to write it at a basic enough level that someone with no exposure to MESA would be able to use it. Since I’m not too sure how the mailing list will handle attachments, I’ve included a link to it below!
> 
> https://drive.google.com/open?id=0B4D4Dndb2klTVUI0TDBJbURvMFk
> 
> Thanks!
> -
> Andrew Mizener
> 
> 
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> _______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users

[mesa-users] Setting up MESA on Amazon EC2 Instances

[Andrew M. <ami...@ma...>]

Hello!

I’m a summer undergraduate researcher. As part of my project, I set up MESA on multiple Amazon EC2 instances. This is a service that allows users to rent remote virtual computers. By using this, I was able to get many more runs with MESA completed than I would have otherwise. My advisor tells me that it would be helpful if I shared my knowledge about this with the MESA community. So, I’ve typed up a guide that explains how one can set up and use MESA with this service. I’ve tried to write it at a basic enough level that someone with no exposure to MESA would be able to use it. Since I’m not too sure how the mailing list will handle attachments, I’ve included a link to it below!

https://drive.google.com/open?id=0B4D4Dndb2klTVUI0TDBJbURvMFk

Thanks!
-
Andrew Mizener

Re: [mesa-users] anyone with access to a Xeon Phi who can test if gfortran now works with it?

[Matteo C. <ca...@ki...>]

Hey Bill,
Yes, I have access to a workstation with a Xeon Phi.
I will have a look and let you know!

-M

-- 
Matteo Cantiello - http://matteocantiello.com/
Associate Research Scientist,  CCA, Flatiron Institute
Visiting Associate Researcher, Princeton University
Chief Scientific Officer and Board Member, Authorea


> On Jul 13, 2017, at 11:58 PM, Bill Paxton <pa...@ki...> wrote:
> 
> I'm considering getting a workstation with a Xeon Phi (Knights Landing) processor for exploring issues with mesa on many cores (> 100).
> 
> This would be made much easier for me if I could use gfortran rather than ifort, but I don't know if that is possible yet.
> 
> Supposedly gcc now works with the Phi, but does gfortran also work?
> 
> Frank pointed me to this link that suggests the gfortran now has caught up and is ready to go on the Phi.
> 
> https://math-linux.com/linux/tip-of-the-day/article/gnu-compilation-for-mic-architecture-knl-knights-landing <https://math-linux.com/linux/tip-of-the-day/article/gnu-compilation-for-mic-architecture-knl-knights-landing>
> 
> If someone with access to a Xeon Phi processor could test a gfortran program on it and let me know, I'd appreciate it.
> 
> Thanks,
> Bill
> 
> 
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot_______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users

[mesa-users] anyone with access to a Xeon Phi who can test if gfortran now works with it?

[Bill P. <pa...@ki...>]

I'm considering getting a workstation with a Xeon Phi (Knights Landing) processor for exploring issues with mesa on many cores (> 100).

This would be made much easier for me if I could use gfortran rather than ifort, but I don't know if that is possible yet.

Supposedly gcc now works with the Phi, but does gfortran also work?

Frank pointed me to this link that suggests the gfortran now has caught up and is ready to go on the Phi.

https://math-linux.com/linux/tip-of-the-day/article/gnu-compilation-for-mic-architecture-knl-knights-landing

If someone with access to a Xeon Phi processor could test a gfortran program on it and let me know, I'd appreciate it.

Thanks,
Bill

[mesa-users] Marlin's request for Tutoring in MESA

[Anandaram M. N. <mna...@gm...>]

Hi:
I have perused the sound advice of MESA experts like fxt etc
I am also a 70+ aged retired guy with PhD in astrophysics and still active
in computational astrophysics using Python with all its add-ons..

If you have a powerful windows computer with i3/i5/i7 Intel chips, 8 to 16
GB RAM,
and 500 to 1000 GB HDD then I can *personally help* you to set up a 100 GB
Linux
Virtual Machine in it through Oracle's VBox. In this LVM we can setup
MESA-SDK from Townsend's
"Mad Star" website and also of course the MESA software (>1 GB size) which
is all in Fortran95.
I will do this *free* but you need to wait till September 2017 when I will
be visiting  Palo Alto for
a few weeks. If this is ok with you we can discuss next moves then. Let me
know

One way to get familiar with what MESA can do is to visit MESAWEB and
download its output files
for your problem.. I did that on June 8th,2015. You can see it at
 http://mesa-web.asu.edu/examples.html
Easier way is to use EZWEB.
Cheers
Mandyam Anandaram

[mesa-users] Job Opening - JINA-CEE Managing Director

[Frank T. <fx...@ma...>]

fyi.

fxt




Managing Director for the JINA Center for the Evolution of the Elements

The Joint Institute for Nuclear Astrophysics Center for the Evolution of the Elements (JINA-CEE) is a multi-institutional NSF Physics Frontiers Center dedicated to bringing together nuclear physicists, astrophysicists, and astronomers to address open questions related to the origin of the elements and the properties of nuclear matter in neutron stars. JINA-CEE consists of a unique network of four core institutions (MSU, Arizona State University, University of Notre Dame, and University of Washington) and 22 associated institutions in seven countries.

JINA-CEE invites applications to fill the position of JINA-CEE Managing Director which is located at the headquarter at Michigan State University (MSU). JINA-CEE seeks a talented and enthusiastic incumbent to lead the day-to-day operation of the center. Examples of responsibilities include: center wide research coordination; contributing to the development of interdisciplinary connections; science communication through print and online media; introduction and integration of new participants; management of workshop, school, and visitor programs; administrative and scientific data bases; content development for websites and social media; authoring reports; assisting in financial planning; and working with JINA-CEE and MSU staff. If of interest, the Managing Director will also be able to carry out a small independent part time research program within the scientific scope of JINA-CEE.

The position is a non-tenure track academic appointment at MSU in East Lansing, Michigan, USA. A PhD in physics, astronomy, or a related field is required. Candidates should have outstanding interpersonal, oral, and written communication skills and a strong interest in science communication and science administration. They should also be self-motivated and able to work independently in a leadership position. No formal management experience is required, but significant experience in management and organizational skills is desirable. Prior experience and/or interest in a research areas broadly related to nuclear astrophysics would also be helpful. Applications from astronomers with these interests are particularly welcome.

Interested candidates should upload a CV and cover letter addressing previous experience in relation to the above stated responsibilities at http://www.careers.msu.edu/ (search for the posting 447849 and follow the application process) and arrange for three letters of reference to be sent directly to:

Prof. Hendrik Schatz
Michigan State University
NSCL
640 S. Shaw Lane
East Lansing, MI 48824, USA
Preferably by e-mail to: sc...@ns...

For questions about the position please contact directly Prof. Hendrik Schatz via e-mail at sc...@ns...

Review of applications will begin on August 15, 2017.

MSU is committed to achieving excellence through cultural diversity. The university actively encourages applications and/or nominations of women, persons of color, veterans and persons with disabilities.

Michigan State University is an Affirmative Action, Equal Opportunity employer.

Re: [mesa-users] Angular momentum loss due to winds

[Glenn-Michael O. <gle...@ku...>]

Note:

Subtracting b% mdot_wind_transfer(b% d_i)? should also do the trick.

________________________________
Van: Glenn-Michael Oomen
Verzonden: woensdag 12 juli 2017 11:09
Aan: mes...@li...
Onderwerp: Angular momentum loss due to winds


Hi Mesa,


There might be a small problem with how the loss of angular momentum due to stellar winds is computed. It appears to me that b% mdot_system_wind is not actually the mass lost due to stellar winds from the system, but the total wind mass loss.


So suppose I would for some reason impose a conservative wind mass transfer such that all the wind is transferred to the companion, then I would expect b% mdot_system_wind(b% d_i) to be zero, which is not the case. The bottom line is that this gives an overestimate for b% jdot_ml.


The issue is in line 290 (and 293) in binary_evolve.f90, where b% mdot_system_wind appears to be defined simply as the wind mass loss of the star. I think that the whole equation should be multiplied by (1 - b% wind_xfer_fraction(s_i)) as to account for wind mass transfer to the companion and vice versa.


Cheers,

Glenn-Michael Oomen

[mesa-users] Angular momentum loss due to winds

[Glenn-Michael O. <gle...@ku...>]

Hi Mesa,


There might be a small problem with how the loss of angular momentum due to stellar winds is computed. It appears to me that b% mdot_system_wind is not actually the mass lost due to stellar winds from the system, but the total wind mass loss.


So suppose I would for some reason impose a conservative wind mass transfer such that all the wind is transferred to the companion, then I would expect b% mdot_system_wind(b% d_i) to be zero, which is not the case. The bottom line is that this gives an overestimate for b% jdot_ml.


The issue is in line 290 (and 293) in binary_evolve.f90, where b% mdot_system_wind appears to be defined simply as the wind mass loss of the star. I think that the whole equation should be multiplied by (1 - b% wind_xfer_fraction(s_i)) as to account for wind mass transfer to the companion and vice versa.


Cheers,

Glenn-Michael Oomen

Re: [mesa-users] Tutoring MESA

[Frank T. <fx...@ma...>]

fine, but be aware that mesa is not supported on windows operating systems.

best wishes in your adventure!

fxt



> On Jul 10, 2017, at 5:26 PM, Marlin Costello <mar...@ya...> wrote:
> 
> Sorry I was a bit hyperbolic, I can handle windows applications where a window requests an entry.  MESA suggests a step beyond windows, which I need some help getting started and set up. Then I can learn to operate this particular software.  That is the tutor I need.
> Marlin
> 
> 
> On Monday, July 10, 2017 4:29 PM, Frank Timmes <fx...@ma...> wrote:
> 
> 
> if you've never operated a computer before, my suggestion is to learn that first. 
> 
> mesa-web assumes one has a working knowledge of how to operate a computer, 
> and mesa assumes one has an even greater degree of fluidity.
> 
> fxt
> 
> 
> 
> 
> 
> > On Jul 10, 2017, at 4:15 PM, Marlin Costello <mar...@ya...> wrote:
> > 
> > Thank you but think that I never turned on a computer before. I need the most fundamental beginning.
> > Marlin
> > 
> > 
> > On Monday, July 10, 2017 4:08 PM, Frank Timmes <fx...@ma...> wrote:
> > 
> > 
> > consider using http://mesa-web.asu.edu - no compiling, no command line, and
> > movies of the results are delivered.
> > 
> > fxt
> > 
> > 
> > 
> > 
> > 
> > > On Jul 10, 2017, at 2:56 PM, Marlin Costello via mesa-users <mes...@li...> wrote:
> > > 
> > > I need tutoring at the most fundamental level in MESA. I can enter data in a windows program but nothing more sophisticated involving language.
> > > I live in Fresno California but I can travel to the Bay area or LA for a few days.
> > > I am 72, an amateur astronomer and will audit a graduate course at CAL in stellar interiors involving MESA.
> > > Can someone work for me at regular tutoring fees?
> > > Marlin Costello
> > > Telescope Garden, Fresno
> > 
> > > ------------------------------------------------------------------------------
> > > Check out the vibrant tech community on one of the world's most
> > > engaging tech sites, Slashdot.org! http://sdm.link/slashdot_______________________________________________
> > > mesa-users mailing list
> > > mes...@li...
> > > https://lists.sourceforge.net/lists/listinfo/mesa-users
> > 
> > 
> > 
> 
> 

Re: [mesa-users] Tutoring MESA

[Frank T. <fx...@ma...>]

if you've never operated a computer before, my suggestion is to learn that first. 

mesa-web assumes one has a working knowledge of how to operate a computer, 
and mesa assumes one has an even greater degree of fluidity.

fxt





> On Jul 10, 2017, at 4:15 PM, Marlin Costello <mar...@ya...> wrote:
> 
> Thank you but think that I never turned on a computer before. I need the most fundamental beginning.
> Marlin
> 
> 
> On Monday, July 10, 2017 4:08 PM, Frank Timmes <fx...@ma...> wrote:
> 
> 
> consider using http://mesa-web.asu.edu - no compiling, no command line, and
> movies of the results are delivered.
> 
> fxt
> 
> 
> 
> 
> 
> > On Jul 10, 2017, at 2:56 PM, Marlin Costello via mesa-users <mes...@li...> wrote:
> > 
> > I need tutoring at the most fundamental level in MESA. I can enter data in a windows program but nothing more sophisticated involving language.
> > I live in Fresno California but I can travel to the Bay area or LA for a few days.
> > I am 72, an amateur astronomer and will audit a graduate course at CAL in stellar interiors involving MESA.
> > Can someone work for me at regular tutoring fees?
> > Marlin Costello
> > Telescope Garden, Fresno
> 
> > ------------------------------------------------------------------------------
> > Check out the vibrant tech community on one of the world's most
> > engaging tech sites, Slashdot.org! http://sdm.link/slashdot_______________________________________________
> > mesa-users mailing list
> > mes...@li...
> > https://lists.sourceforge.net/lists/listinfo/mesa-users
> 
> 
> 

Re: [mesa-users] Tutoring MESA

[Frank T. <fx...@ma...>]

consider using http://mesa-web.asu.edu  - no compiling, no command line, and
movies of the results are delivered.

fxt





> On Jul 10, 2017, at 2:56 PM, Marlin Costello via mesa-users <mes...@li...> wrote:
> 
> I need tutoring at the most fundamental level in MESA. I can enter data in a windows program but nothing more sophisticated involving language.
> I live in Fresno California but I can travel to the Bay area or LA for a few days.
> I am 72, an amateur astronomer and will audit a graduate course at CAL in stellar interiors involving MESA.
> Can someone work for me at regular tutoring fees?
> Marlin Costello
> Telescope Garden, Fresno
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot_______________________________________________
> mesa-users mailing list
> mes...@li...
> https://lists.sourceforge.net/lists/listinfo/mesa-users