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[Walter Landry]

Hi,

Sorry this took so long.  I am Cc'ing the cig-seismo list in case
anyone else has these issues.

Shin-Chan Han <Shin-Chan.Han at nasa.gov> wrote:
> Hi again,
> 
> I think the normalizaton factor for frequency is
> 
> sqrt(G*rho_n/4/pi)

So are you saying that there is a factor of 2*pi missing?

> Also l*(l+1) factor needs to be multiplied to V^2(r) in the integral,
> because nVl(r) Mineos outputs is not scaled by 1/sqrt(l*(l+1)).

The comments in the code agree with you.  It is hard for me to verify
by just looking at the code.  What test did you run to figure this
out?

> Mineos output is the nVl(r) appeared in Gilbert and Dziewonski (1975),
> but NOT nVl(r) used in Aki and Richards text.  <= Please confirm this.

I do not know.  The manual references Gilbert and Dziewonski but not
Aki and Richards.  So I would presume that you are correct.

> On 6/10/10 10:31 AM, Shin-Chan Han wrote:
>> Hi Walter,
>>
>> I just finished MINEOS run and got some values for radial normal mode
>> including nUl(r) and nVl(r).
>>
>> I tried to test normalization shown in page 21 of the MINEO document.
>>
>> I understood this as follows:
>>
>> 1) I take U(r) and V(r) from the runs
>> 2) I take rho from Earth model (PREM) and divide it by reference value
>> 5515
>> 3) the radius is divided by 6371d3
>> 4) compute the integral with those dimensionless values as given in
>> the
>> equation in page 21.
>> 5) the integral should be square of period (inverse frequency) after
>> normalization of frequency
>> 6) Is the frequency normalization written correctly? Even physical
>> dimension of the formula as written in page 21 is not correct.

I presume you mean page 23.  The frequency normalization has the right
units.  Frequency = 1/time, and the normalization is velocity/length.

>> Do you also have a sample plot for any U and V function so that I can
>> check my run is ok.

I do not have that.  You can run the benchmarks and make sure that you
get the same results.

Cheers,
Walter Landry
walter at geodynamics.org