[Message Prev][Message Next][Thread Prev][Thread Next][Message Index][Thread Index]
[vsnet-campaign-nova 953] Re: V2540 Oph - detection of period/s
Dear Taichi,
I really can't understand your hostility. You are right in certain points,
but wrong in others. I don't have time to continue this debate for ever.
To summarize my point, which unfortunately hasn't been understood so far):
1. There is still an argument on the nature of the transition phase,
although we are very close to the solution.
2. Four years ago I suggested that it appears only in intermediate polars.
See: Retter, Liller & Garradd, 2000, in Charles P., King A., O'Donoghue
D., eds, Proc. of Cataclysmic Variables: a 60th Birthday Symposium in Honour
of Brian Warner, special edition, p65
This was based on the FACT that the observations of novae were consistent
with this connection.
3. This gives a simple prediction: novae that have the transition phase
should be intermediate polars.
4. As ~10% of CVs are classifies as intermediate polars, this idea also
gives a simple explanation to the question why only ~15% of the nova
population have the transition phase.
5.. Since then observations of 3 or 4 novae are consistent with this idea.
The prediction is then highly (97-99%) significant.
6. It is possible that the physical mechanism may be connected with Nir
Shaviv's ideas.
Let the other observers decide whether they are waisting their time
observing Nova V2540 Oph 2002. In the worst case they will find new
period/s in novae instead of new superhump periods in SU UMa systems.
I do not tend to spend more time on this matter.
Regards,
Alon
-----------------------------------------------------------------------
Dr. Alon Retter Tel. (work) +61-2-9351-4058
School of Physics Fax (work) +61-2-9351-7726
University of Sydney -------------------------------------------
Sydney, 2006 'As a scientist I don't believe myself, so
Australia why should I believe you?' (A.R. 1965-2085)
-----------------------------------------------------------------------
On Fri, 2 Aug 2002, Taichi Kato wrote:
> 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
>
>
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page