On 18 Feb 2007 19:20:31 -0800, "Leonard Kellogg" wrote:

Henri Wilson wrote:


The 'bunching of pulses' I refer to is not the same.

Are you saying that light pulses emitted by pulsars bunch
in a manner different from that of light pulses emitted by
other types of star?

Well basically no.... but it is the way they are handled
that matters. Pulsar pulses don't become any more intense
just because they 'bunch'. Nobody talks about the brightness
curve of a pulsar because the pulses are very constant.

What distinguishes pulsar light from other starlight is that
it is *not* constant. Is that a problem for your program?
The bunching process is the same, but your program is
designed to represent brightness changes in a continuous
stream of light, not in a chopped stream?

You said, 'The program assumes the star emits identical
pulses of light towards the observer at regular intervals
as it moves around its orbit...'

If it can handle pulses of light from a regular star, why
can't it handle pulses of light from a pulsar?

It can... but the answer it produces is in the form of a brightness curve, not
the bunching factor. One doesn't hear of 'brighness curves of pulsars'. The
pulses are constant even if their arrival rate is not.

I use symbolic pulses from a star of constant brightness
emitted at equi-temporal points around the orbit. These
travel at varying c+cos(v) speeds towards a distant obsever.
The rate at which they arrive at the observer should then
simulate its brightness curve there.

So apply that to the pulsar.

There is absolutely no point....unless you can provide a reliable curve showing
the variation in arrival rate of the pulses over time. That should be the same
as my 'brightness curve'. I can't make sense of the curve published by Jacoby
et al

Also, I cannot adjust the number of pulses I sample per orbit (122 million in
this case) without changing the code a bit. I can do it but it will take a
little time


Aside from dwarf novae, the only regularly-variable dwarf
stars I know of are ZZ Ceti variables. Wikipedia says:
"These non-radially pulsating stars have very short periods
of 0.5 to no more than 25 minutes with tiny fluctuations of
0.001 to 0.2 magnitudes."

there are millions of stars varying by 0.3 to 1.6 mags.
Cepheids (as they are broadly named) are the most interesting.

The star you asked for information about is a white dwarf.
I responded with relevant information about white dwarf
variability. We are not concerned at the moment with
other star types.

provide me with a good curve of pulse arrival times and i can probably do what
you ask.


Leonard