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[vsnet-campaign-nova 952] Re: V2540 Oph - detection of period/s
Re: V2540 Oph - detection of period/s
Dear Alon,
> > Could you explain the point you thought that the paper is "nice"?
> > (As everyone knows, not all papers are nice...)
>
> The point was that the paper was full of physics and explained nicely
> the problem. I must say, however, that I didn't go into details. When I
> read the paper it was already known that there are magnetic novae.
That was a letter (rather than a full paper). Such a letter usually
presents only an outline of the idea (I wonder what was full of physics
you are referring to?) to explain some of observational characteristics.
The paper was correct in this viewpoint, which enabled a quick and more
detailed formulation when the new observational fact becomes available.
This paper didn't say "why novae can't be magnetic" (you stated
in vsnet-campaign-nova 947). Please reread the paper and understand
the contents more properly.
> > This is not a common belief. There still exists an argument among
> > theoreticians.
>
> This was the common belief.
I don't think so. Even in 1994 (before superhumps were discovered
in V1974 Cyg), I remember I had a dicussion regarding this problem.
There still remains an argument (both from theories and observations).
[Perhaps your "theoreticians" refer to some special group?]
> > No one has ever denied the possibility of a nova from an AM CVn-type
> > object. You may have mistaken the argument against your talk; that was
> > against your unification scheme between classical novae and X-ray novae
> > (I remember someone asked what are X-ray novae you were referring to).
>
> Sorry, but you are wrong about it. Most theoreticians hate this idea.
Hate what idea? A unification scheme between classical novae and X-ray
novae? ;-)
> 1. there is not enough energy in helium burning on the shell for a nova.
> 2. it will become a supernova (the burning will reach the core).
If you are referring to helium ignition on a white dwarf, these
points are one of major concerns by (some) theoreticians (although I don't
quite understand the meaning of the argument 1). However, at least the
second point has been discussed for a long time.
The possibility of helium iginition on a white dwarf was proposed
long time ago. The possibile consequence of type-Ia supernovae has also
been widely known. Then what is your contribution in the presence of
these modern calculations?
> Yes, it could be a supersoft X-ray source, but as novae usually turn off
> in the X-ray after 1-2 years the simplest explanation is that this is an
> intermediate polar.
Explain the energetics. Supersoft X-ray sources emit nearly Eddington
luminosity. Explain how an intermediate polar can emit a comparable
X-ray luminosity.
> I've actually discussed my idea with a few theoreticians who inspired me
> to change the initial model.
Reading all your explanations, I'm skeptical if your theoreticians
serously considered your model or your have been correctly inspired of
new ideas.
Before concluding your remarks, please show the predictive power of
your "model" and your understanding. I list the questions you have not
properly answered:
1) How magnetosphere interacts with the disk to produce oscillations?
What is the necessary magnetic field? What would be the oscillation period?
Why such oscillations are not observed except during the transition phase?
A real "predictive power" would be able to, at least in some part, give
an answer.
2) > You surely remember how several
> theoreticians strongly attacked this idea I presented in the Kyoto
> conference a few years ago.
You may have mistaken the argument against your talk; that was
against your unification scheme between classical novae and X-ray novae
(I remember someone asked what are X-ray novae you were referring to).
Any comment on this?
> I hope that the argument is over now. I've understood your point, and I
> hope that you have understood mine.
--- I hereby summarize my understanding ---
(1) Some novae show oscillations during their "transition phase".
(2) Alon Retter has been considering that these phenomena are somehow
related to intermediate polars, but has not been able to construct a physical
and consistent model. No quantitative predictions have been ever made.
(3) In the meantime, Nir Shaviv recently proposed a promising idea
as a natural consequence of an instability in the nova winds. Shaviv
also succeeded in explaining why super-Eddington phase in novae lasts more
than the dynamical time, and explaining the previously noticed discrepancy
of mass-loss rates between theories and observations.
(4) Nevertheless, Alon Retter claims that his "model" is no worse than Nir
Shaviv's and actually has an advantage.
(5) Alon Retter's ideas have been repeatedly and repeatedly attacked by
most theoreticians. He confessed that at least one of his ideas met
"strong hostality of most theoreticians". Nevertheless, Alon Retter think
these theoreticians were wrong.
(6) Alon Retter hasn't made an objection against the idea that "without
a physical basis, we can't tell the differecence between the claimed
predictive power and fortune-telling."
(7) I hope wise observers on this list has understood how to make a
distinction between a logical and constructive theory and a fabulous
fortune-telling (please make a distinction by yourself; I don't say which
is which). My hope is that precious telescope time would not be wasted
in a fabulous fortune-telling.
Regards,
Taichi Kato
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