Mathias wrote:

Dear Rich

Does GYRE 5.0 still have the option to return the "normalized rotation kernel" (parameter "K") in the output mode files?

GYRE 4.4 had this option, but version 5.0 doesn't seem to have this parameter. Did you maybe remove this feature on purpose?

Best regards

Mathias

Dear Rich

Does GYRE 5.0 still have the option to return the "normalized rotation kernel" (parameter "K") in the output mode files?

GYRE 4.4 had this option, but version 5.0 doesn't seem to have this parameter. Did you maybe remove this feature on purpose?

Best regards

Mathias

GYRE 5.0 returns either the Ledoux coefficient (C) or its gradient (dC_dx). The gradient is equivalent to the unnormalized rotation kernel.

My recollection is that K can be reproduced by some combination of these -- but you may have to do some digging. I haven't touched this code for a while.

cheers,

Rich

Statistics: Posted by rhtownsend — Sat Feb 18, 2017 11:04 pm

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Does GYRE 5.0 still have the option to return the "normalized rotation kernel" (parameter "K") in the output mode files?

GYRE 4.4 had this option, but version 5.0 doesn't seem to have this parameter. Did you maybe remove this feature on purpose?

Best regards

Mathias

Statistics: Posted by Mathias — Sat Feb 18, 2017 8:57 am

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richakundu wrote:

hello rich

i am again having an issue with new version. I want my output frequencies in per day unit.

I tried t add

freq_units='PER_DAY'

in the summery file but its not accepting this unit. If i give

freq_units='HZ'

the program runs perfectly fine but omega that i get is still dimensionless frequency.

plz help...

Richa Kundu

hello rich

i am again having an issue with new version. I want my output frequencies in per day unit.

I tried t add

freq_units='PER_DAY'

in the summery file but its not accepting this unit. If i give

freq_units='HZ'

the program runs perfectly fine but omega that i get is still dimensionless frequency.

plz help...

Richa Kundu

Hi Richa --

You should be using 'CYC_PER_DAY', not 'PER_DAY'.

Also, 'omega' Is always the dimensionless frequency. For the dimensioned frequency, you need 'freq'.

cheers,

Rich

Statistics: Posted by rhtownsend — Thu Feb 16, 2017 9:22 am

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mankovich wrote:

Hi Rich (and fellow GYREators),

Can I ask you to elaborate a little bit on what the tables contain? Am I right in thinking that the tables contain coefficients to Chebyshev polynomials fit to solutions for the Hough eigenvalues obtained numerically?

(For a little context, I started digging around when I noticed that the traditional approximation only works for l≤3 as a result of the coverage of gyre/data/trad_table.h5. I suppose to calculate the eigenvalues on the fly as part of a GYRE calculation would be significantly more complexity than it's worth!)

Cheers,

chris

Hi Rich (and fellow GYREators),

Can I ask you to elaborate a little bit on what the tables contain? Am I right in thinking that the tables contain coefficients to Chebyshev polynomials fit to solutions for the Hough eigenvalues obtained numerically?

(For a little context, I started digging around when I noticed that the traditional approximation only works for l≤3 as a result of the coverage of gyre/data/trad_table.h5. I suppose to calculate the eigenvalues on the fly as part of a GYRE calculation would be significantly more complexity than it's worth!)

Cheers,

chris

Hi Chris --

Sort of! The Chebyshev fits are to lambda/(l(l+1)) for |nu| < 1, where lambda is the Hough eigenvalue.

For |nu| > 1, the fits are to the ratio lambda/lambda_asymp, where lambda_asymp is the asymptotic eigenvalue found in Townsend (2003).

In the latest version of GYRE (5.0, currently pre-release), I extend the fits up to higher l,m (10, I think). Also, I use an improved routine for calculating the eigenvalues, and an improved asymptotic formula for lambda_asymp.

You're right that fits are used for efficiency reasons -- in differentially rotating stars lambda must be evaluated at each grid point, which can be very time consuming if we're doing it on-the-fly.

cheers,

Rich

Statistics: Posted by rhtownsend — Wed Feb 15, 2017 12:41 pm

]]>

I tried t add

freq_units='PER_DAY'

in the summery file but its not accepting this unit. If i give

freq_units='HZ'

the program runs perfectly fine but omega that i get is still dimensionless frequency.

plz help...

Richa Kundu

Statistics: Posted by richakundu — Wed Feb 15, 2017 1:13 am

]]>

Can I ask you to elaborate a little bit on what the tables contain? Am I right in thinking that the tables contain coefficients to Chebyshev polynomials fit to solutions for the Hough eigenvalues obtained numerically?

(For a little context, I started digging around when I noticed that the traditional approximation only works for l≤3 as a result of the coverage of gyre/data/trad_table.h5. I suppose to calculate the eigenvalues on the fly as part of a GYRE calculation would be significantly more complexity than it's worth!)

Cheers,

chris

Statistics: Posted by mankovich — Tue Feb 14, 2017 6:31 pm

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Thank you very much for clarifying my questions. It is very helpful . Have a nice day .

Sincerely,

Jing

Statistics: Posted by jingluan — Thu Feb 02, 2017 3:51 pm

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jingluan wrote:

Hi Rich,

Thank you for answering my questions about the convection zone .

For the optically thin part of the stellar model, does gyre not calculate any non-adiabatic effect please? I ask this question because the mesa model I use includes the part with optical depth << 2/3. So I am wondering how gyre treats the energy equation in this part please.

Many thanks!

Sincerely,

Jing

Hi Rich,

Thank you for answering my questions about the convection zone .

For the optically thin part of the stellar model, does gyre not calculate any non-adiabatic effect please? I ask this question because the mesa model I use includes the part with optical depth << 2/3. So I am wondering how gyre treats the energy equation in this part please.

Many thanks!

Sincerely,

Jing

Hi Jing --

GYRE does not distinguish between optically thin and optically thick regions. So, in the optically thin region the diffusion equation is still used to calculate the radiative flux. This is a crude approximation, but has little effect on the global stability (or instability) of modes. In the near future, I plan to replace the diffusion approximation with the Eddington approximation, which works well in both optically thin and optically thick limits.

cheers,

Rich

Statistics: Posted by rhtownsend — Thu Feb 02, 2017 3:48 pm

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Thank you for answering my questions about the convection zone .

For the optically thin part of the stellar model, does gyre not calculate any non-adiabatic effect please? I ask this question because the mesa model I use includes the part with optical depth << 2/3. So I am wondering how gyre treats the energy equation in this part please.

Many thanks!

Sincerely,

Jing

Statistics: Posted by jingluan — Thu Feb 02, 2017 3:37 pm

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jingluan wrote:

Hi Rich,

Another question please , to make sure I understand you.

By 'convection frozen', do you mean that gyre ignores the fact that convection can mix the entropy perturbations throughout the convection zone please?

Thank you very much

Sincerely,

Jing

Hi Rich,

Another question please , to make sure I understand you.

By 'convection frozen', do you mean that gyre ignores the fact that convection can mix the entropy perturbations throughout the convection zone please?

Thank you very much

Sincerely,

Jing

No, I don't think so. 'Frozen convection' is simply the common way of saying that the effects of pulsation on convective energy transport are neglected.

Statistics: Posted by rhtownsend — Thu Feb 02, 2017 3:08 pm

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jingluan wrote:

Hi Rich,

Thank you so much for your quick response May I ask what you mean specifically (exactly) by

'the convective heating/cooling term in the energy equation' please? Do you mean that gyre ignores the perturbation to the background(unperturbed-state) entropy gradient please?

Sincerely,

Jing

Hi Rich,

Thank you so much for your quick response May I ask what you mean specifically (exactly) by

'the convective heating/cooling term in the energy equation' please? Do you mean that gyre ignores the perturbation to the background(unperturbed-state) entropy gradient please?

Sincerely,

Jing

Being specific, GYRE ignores the perturbations to the term

rho^{-1} div F_c

in the energy equation, where rho is the density and F_c is the convective flux. There are a number of other ways to 'freeze' convection -- see Unno et al, 1989 (Nonradial oscillations of stars).

cheers,

Rich

Statistics: Posted by rhtownsend — Thu Feb 02, 2017 3:04 pm

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Another question please , to make sure I understand you.

By 'convection frozen', do you mean that gyre ignores the fact that convection can mix the entropy perturbations throughout the convection zone please?

Thank you very much

Sincerely,

Jing

Statistics: Posted by jingluan — Thu Feb 02, 2017 3:03 pm

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Thank you so much for your quick response May I ask what you mean specifically (exactly) by

'the convective heating/cooling term in the energy equation' please? Do you mean that gyre ignores the perturbation to the background(unperturbed-state) entropy gradient please?

Sincerely,

Jing

Statistics: Posted by jingluan — Thu Feb 02, 2017 3:00 pm

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jingluan wrote:

May I ask for a reference explaining how gyre calculates non-adiabatic effect please?

I am interested in g modes in white dwarfs. There is an outer convection zone. Does gyre only calculate non-adiabatic effect due to photon diffusion please? If yes, how does it treat the non-adiabatic effect in the convection zone and the atmosphere above the photosphere please?

Many thanks.

Sincerely,

Jing

May I ask for a reference explaining how gyre calculates non-adiabatic effect please?

I am interested in g modes in white dwarfs. There is an outer convection zone. Does gyre only calculate non-adiabatic effect due to photon diffusion please? If yes, how does it treat the non-adiabatic effect in the convection zone and the atmosphere above the photosphere please?

Many thanks.

Sincerely,

Jing

Hi Jing --

Thanks for your question. GYRE currently includes non-adiabatic effects due to radiative transport, as modeled by the radiative diffusion equation. These effects are included in both radiative and convective regions. However, in convection regions the convection is frozen by ignoring the perturbations to the convective heating/cooling term in the energy equation.

cheers,

Rich

Statistics: Posted by rhtownsend — Thu Feb 02, 2017 2:52 pm

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