Re: Swift grb satelitte


jaymoseley@xxxxxxxxxxx (sean) writes:
> Craig Markwardt <craigmnet@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:<onll7pk9ry.fsf@xxxxxxxxxxxxxxxxxxxx>...
> >Do you have any examples where data was *REQUIRED* to be released but
> >was not?
>
> I required them to be released.

Irrelevant. Your requirements are not part of the Swift mission.

I also note that you ignored the fact that light curves and spectra
*are* released via GCN notices, and in some already-published papers.

> >It was *you* that claimed that GRB time delays
> >are proportional to wavelength, and *you* that claimed they were also
> >proportional to the *difference* in wavelength. These are
> >contradictory claims,
>
> You have still yet to show how these two are different. For instance
> which of the two does *not* mean that the delay increases
> proportional to the increase in wavelength?

I note that you deleted *yet again* an example which shows the
contradictory nature of your two claims. You could have researched
the definition of "proportional" but did not.


> >> I find this conclusion of gcn 2916 odd. How is it that a...
> >> " drop-off with decreasing wavelength is gradual" as it says
> >> in the post, equate with a low redshift grb?
>
> >Three words: Lyman alpha forest.
>
> The Lyman break is a sharp break whereas there is a

This claim is not true, therefore the conclusions you draw based on it
are irrelevant.
....


> >Again, you conveniently deleted an important part of my post,
> >which regarded *formal* *statistical* *tests*. The kind of
> >tests which have a null hypothesis, a statistical test, and
> >confidence limits on parameters. And of course, proper
> >treatment of error bars and upper limits. And the point is
> >that right now you are using a trial-and-error approach which:
> >(a) ignores many possible combinations of valid parameters
> >which may not be so flattering to you; (b) ignores
> >uncertainties on measurements; and (c) ignores possible
> >systematic biases.
>
> Which parameters am I ignoring? You have to be more specific.

http://mathworld.wolfram.com/Proportional.html

If 'a' is (directly) proportional to 'b', then 'a/b' is
constant. The relationship is written , which implies 'a = c b' for
some [proportionality] constant 'c'.

The proportionality constant between wavelength (*) and time is the
adjustable parameter of your model, whether you realize it or not.

(*) - or difference in wavelength, for your other contradictory claim.

> Regarding uncertainties in measurements I think you make the
> mistake you did when you asked for a chi^2 fit to test my model.
> You cant smooth out the variabilities in the lightcurves as if
> grb`s were explosions with decay afterglows. ...

I didn't ask for a chi^2 fit to test your model. What I did suggest
is that some kind of formal statistical test which addresses
measurement uncertainties, upper limits, and derives parameter
confidence regions, is required. I note your diversion to the
"smoothing" topic.


> And regarding systematic biases once again you will have to be
> more specific. Biases in what systems? The observations?

"Systematic bias" has a well-defined meaning, and addressing it is
crucial to most scientific research.

> You either dont understand my model or if you do you pretend
> you dont because I think the fact is that this requests is
> irrelevent to this dicussion
> For instance if you pretend to understand my model then tell
> me what systematic biases are you referring to? And how do these
> supposed biases affect the predictions I have made?

That would be your problem, not mine. There are obvious selection
effects which would lead to biases. For example, optical/IR
observations can usually be done the night of the GRB, but as a
practical matter, sensitive radio observations often take longer to
schedule. This would naturally lead to a gamma-ray - then optical/IR
- then radio progression of detections. But of course this only
reflects the order of *observations*, not the presence of emission,
nor a "peak" in the emission.

....

> >What does your model "explain?" It contains no physics.
> >It contains no useful information about GRBs. Meanwhile,
> >other works *do* contain physics, and thus they have the
> >advantage, because they are constrained by reality, whereas
> >you are not.
>
> This is a ridiculous statement. My model explains grb`s.
> Correctly and backed up with verification by observation
> unlike beamed theory. And yes,of course it contains physics.
> It is the physics of wave propogation of emr . This has been
> around for centuries and is one of the oldest, best studied
> fields in physics.

Yes, and for a century, it has been known that electromagnetic
radiation travels at a constant speed at all wavelengths. Thus your
"model" is utterly erroneous.

Of course, if as you claim, that GRBs are simply upshifted starlight,
then the spectra in other wavelength bands should be stellar spectra
-- BUT THEY ARE NOT. In fact, gamma-ray burst spectra have well known
bent power law spectra (stars do not). X-ray spectra of afterglows
are power laws (for stars they are not). The optical/IR spectra of
GRB afterglows do not match optical/IR spectra of stars. Stellar
spectra typically have systems of absorption and emission lines
superimposed on a thermal continuum -- GRB spectra at all wavelengths
are not like this. Thus your model is multiply erroneous.

....
> >I note that you did not actually read astro-ph/0503508 or
> >astro-ph/0503521, which both show *observed* prompt optical
> >emission for GRBs 990123 and 041219a.
>
> Your two papers speculate that prompt optical emmision may
> have occured but the fact is that there is no observation
> that was made in optical at the time of trigger in gamma.

This is an erroneous claim. In fact, for GRB 041219a, optical
observations were taken during the peak of the gamma-ray burst, and
optical emission was detected (see citations given). Thus, "zero"
delay between gamma-ray and optical wavelengths is possible.


> Neither grb was observed before or at the same time as the
> burst was first observed in gamma. 041219a for instance was
> only observed *after* the first trigger
> in gamma . My model doesnt preclude any wavelength being
> observed while still observable in a shorter wavelength. It
> only precludes any wavelength peaking at the same time as
> any other shorter (or longer)
> wavelength. Your argument here is a non starter.

Ironic, since in the case of 041219a, the optical emission peaked at
the time of the gamma-ray peak. It looks like the preclusion of your
model is incorrect.

> >Let's get one thing straight. Electromagnetic radiation,
> >up and down the spectrum, behaves in fundamentally the
> >same way. Most importantly, it all travels at the speed
> >of light, c. Thus, if radio waves from pulsars; microwaves
> >from AGN and GPS satellites; X-rays from pulsars,
> >gamma-rays from soft gamma repeaters and pulsars, all
> >behave in the same way, then you have a serious problem
> >explaining how GRBs are magically special and don't behave
> >like other electromagnetic phenomena. Here again, the
> >lack of any physics in your "model" makes
> >it virtually useless at "explaining" anything.
>
> ....
> What I am
> doing instead is showing how in a infinite non expanding model
> where c is variable one can model the way emr behaves

This is again ironic, since you appealed to the authority of more than
a century of research on electromagnetic research above. And that
research demonstrates that the speed of light is constant, *not*
variable.


> ... that can
> explain grbs as the light from a very distant source that is
> being rapidly redshifted over short periods of time. ...

Are you really claiming that gamma-ray bursts are heavily
*redshifted*? Since the only way to make gamma-rays from *anything*
is by blue-shifting, your "model" would have a serious error.


....
> >> You conveniently ignore the many times in previous posts where I say
> >> that ground based spectra invariably have contamination from intervening
> >> or nearby galaxies stars etc.
> >Of course, this claim is unsubstantiated. Which stars and galaxies?
> >In fact, many ground based observatories have much *higher* spatial
> >and spectral resolution than Swift does, and *comparable* resolution
> >to the Hubble space telescope. Thus spectra and images taken by
> >ground based instruments can be as good as, or better than, spectra
> >and images taken by Swift or Hubble. If you had looked at any ground
> >based images you would have found that is in fact uncommon to have a
> >contaminating (i.e. overlapping) galaxy or star.
>
> Redshifts from ground based spectra are always made post burst after
> the optical peak and at mag similar to the so called host galaxy

Irrelevant. The imprint of redshifted absorption features will appear
on both the afterglow spectrum and the host galaxy spectrum (if any).
See "lyman alpha forest" again.

> >I note that you don't substantiate how the atmosphere would
> >"contaminate" a spectrum, as regards to redshift determination.
>
> I admit Im not an expert on how atmosphere affects observations
> but I assume that if the atmosphere is a gas. And if far less
> dense gases like intervening cosmological gas clouds can produce
> lines then why couldnt the earths atmosphere, being far more dense,
> do the same and to a greater degree ?

The spectral features of the earth's atmosphere are well known and do
not vary in wavelength. Thus, these features can be identified and
ignored. The careful study of redshifted absorption features has a
long history and the techniques are well understood.

....
> >Second of all, even a cursory look at real GRB afterglow light curves
> >would show that they *are* well sampled from ground based telescopes,
> >and they do *not* show multi-peaked profiles. A review such as Berger
> >et al. (astro-ph/0502468) shows this beautifully.
>
> Look at fig 5 from your cited paper and there
> are at least 5 different lightcurves from the many on the graph
> that show at least several rebrightenings each. And those are
> long exposure datapoints that are spaced out by hours and days
> apart. The exposures themselves average out fluctuations during
> the exposure to one set value and the lack of other data
> between observations disguises numerous possible rebrightenings.
> How can you even pretend that where there is no data between
> exposures that the decay rate is a straight
> line between two adjacent datapoints when in many cases the
> decay rate between any three exposures is variable.

Pretense is not needed. Your claim is that the optical light curve
should be a stretched version of the gamma-ray light curve. In fact,
most of the light curves shown in the Berger paper are very well
sampled -- sampled enough to show a stretched version of the gamma-ray
light curve -- and look nothing like the gamma-ray light curve.


>
> > Most obviously, all
> >GRB afterglows are predominantly *decaying* profiles, whereas GRB
> >profiles are peaked profiles. No amount of resampling will change a
> >decaying profile into a peaked one. Thus, your supposition is
> >erroneous.
>
> I`ve worked alot in photography and I know that if I
> had a light source that over a period of lets say 10 minutes faded
> from very bright A to nothing B but during the decay was variable
> like this..
> A X Y Z
> .
> . .
> . .
> . . . .
> . . . . .
> . . . B
> If I then took three exposures one (X)between 0-1 minutes the
> second (Y)between 4-5 minutes and the third (Z) betweeen 7-8
> minutes
> I would probably get this decay lightcurve...
> A X Y Z
>
> .
> .
> .
> B
>
> As you can see, contrary to your above claim ,resampling, ie
> different bin times at different sampling rates, *can* change
> the decay profile from multipeaked into a flatline decay slope.

Your analogy is irrelevant. In fact, the exposure times are short
compared to the time span of the overall light curves. This is
especially true on a logarithmic time axis. The optical light curves
are well enough sampled to detect a stretched version of the gamma-ray
light curve. With the existing sampling, there is really no way for
an optical light curve which decays by many orders of magnitude to be
mistaken for a gamma ray burst light curve.

> >My mistake. I meant GCN 298, which has a true IPN error box,
> >independent of other techniques [, plus a hybrid IPN+RXTE box.]
>
> I dont quite understand you here. It is clearly a IPN Hybrid in
> that it is an IPN overlap of an existing Batse box and yet you
> seem to be pretending that it is a time of arrival only. It isnt.
> Look at gcn 290 which was the first gcn made for 990506 and the
> first of several IPN localizations released. And it (290) was
> made AFTER the BATSE box was known. How could it be a time of
> arrival only localization if BATSE supplied a error box before
> the IPN was calculated? Not only that both 290 and 298 clearly
> state that BATSE had made a localization prior to IPN.
....
> .... And they were made and available *before* IPN calculated
> its annulus And finally IPN was aware of these error boxes before
> they calculated their annulus.

Again irrelevant. The whole point is for the IPN to make an
independent solution with the timing data only. Professional science
is not elementary school, and there is no need to manipulate the
results. The physics and geometry that underlie the IPN technique are
very simple.


> >I note that you continue to make an unsubstantiated claim that somehow
> >the IPN analysis "fit[s] [or] manipulate[s] their annulus to these
> >boxes." In the past you have complained that the raw IPN data was not
> >provided. Both of these claims are erroneous. In fact, the data
> >*have been* provided, in the form of two papers by Laros et
> >al. (citations previously given), which you continue to ignore. And
> >in fact, the IPN analysis is a very simple application of
> >triangulation which does not involve fitting or manipulating positions
> >at all.

I note your continued lack of substantiation on your manipulation
claim. You could have analyzed the Laros data to substantiate your
claims of manipulation, but did not.

> And I checked those dates you give for Laros. 97 does not seem
> to have a Laros paper I can find. Only 98 is available and it
> seems to only cover 90-93 in grb data.

There were two papers. The citations have been provided multiple
times, but as a kindness I have repeated them below.

> And as far as I am aware
> no OT was ever made of a grb till after these dates so how can
> this paper supply time of arrival locations that can be verified
> seperately by Optical or radio observations?

Irrelevant. Both Laros et al. papers show that IPN solutions are
consistent with GRO error boxes, and show that IPN solutions are
consistent with each other (in cases where multiple satellites are
involved). Your "model" would predict neither of those facts.


> I also would like to say that the data isnt sufficient for me
> to use from it anyways. There doesnt seem to be any obvious way
> for me to check the physical locations in 3-d of the seperate
> satelites so that
> I can work out the IPN location relative to the location of the
> satelites. It would have to have some sort of x y z coordinates
> and they would have to be the same system as the localization
> coordinates.

The locations of the IPN spacecraft are provided in each Laros et
al. paper, and they are given in the same coordinate system as the GRB
localizations. Thus your preconditions have already been met. The
rest is your problem.

At this stage, I note that you continue to make speculative and
unsubtantiated claims, you continue to decline to research even the
most basic aspects of your claims (for example the definition of
"proportional"), and you continue to selectively edit postings to
confound the debate (for example, your contradictory claims on
proportionality). As you write more on your model, you dig yourself
deeper into trouble (for example, you claim gamma-ray bursts are
redshifted!). It is clear that you have some very fundamental
problems, which I cannot help with.

CM


References

Laros, J., et al. 1997, Ap. J. Supp. Ser. 110, 157
Gamma-Ray Burst Arrival Time Localizations: Simultaneous
Observations by Mars Observer, Compton Gamma-Ray Observatory, and
Ulysses, (9 bursts, 1992-1993) - coincident GRO + IPN boxes

Laros, J., et al. 1998, Ap. J. Supp. Ser. 118, 391
Gamma-Ray Burst Arrival Time Localizations: Simultaneous
Observations by Pioneer Venus Orbiter, Compton Gamma-Ray
Observatory, and Ulysses (arrival times given) (37 bursts, 1991-1992)

.