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Re: swift grb data rules out beamed theory

Subject: Re: swift grb data rules out beamed theory
From: "sean"
Date: 29 Mar 2006 15:31:46 -0800
Newsgroups: sci.astro
"sean" <jaymose...@xxxxxxxxxxx> writes:


...


> The fact is  I never said redshifts of grbs couldnt
> be measured. I said the following...

> "Any apparent point like source is an illusion and this
> may be shown by SWIFT by there being no observable or
> confirmable z value....If SWIFT is able to take multiple
> spectrum images of early optical bursts in the first few
> hours post grb detection..."


> Notice I specifically say *Swift* , in the context of
> *spectra* of OT`s.  Which I refer to several times in
> the paragraphs following that quote.  As far as I`m
> aware Swift has yet to supply a spectral redshift in
> Optical of any GRB. Have you access to information it
> does? I doubt it.


Craig..
Your claim is not quite true (e.g. GCN 3923).  However, even if it
*were* true, it is irrelevant.  Even though it's possible for Swift to
detect a burst, but some other observatory detects the fading
afterglow and determines its redshift, the redshift is still valid.

Sean..
Ive checked out 3923. Thats a `no detection` in 6 wavelength
bands.
Not a continuum with absorbtion and emmision lines.
The ground based spectra isnt valid in my opinion. But we
argued this before Swift went up. And neither of us agreed
for all the reasons available in other threads. Thats on
record.But thats why in 2004 I decided to make a prediction
that a space based Swift spectra would be unable to give
any clear redshift as opposed to those ground based
suppositions which we dont agree on. And thats the
prediction that still stands. Unfortunately at the time
I misunderstood Swift capabilities and assumed it could
supply those spectra. And it doesnt, not in optical.
Anyways you try to shift the argument away from one
prediction that is verified that you claimed was never
possible, which is why I started this thread.
You do this to avoid admitting I was right all along to
criticise power law fitting of grb lightcurves. Thats an
a priori prediction on my part and you cant deny that.
After all , before Staneks paper it was assumed that
fluctuations werent real or theoretically possible.
They stil arent explained and I predicted theyd be
there and explained why power law smooothing was
unscientific. Its all in the first post of this thread
as far as your quotes and those from others, my
predictions and Staneks quotes confirming you were
wrong and I was right.
> Craig tried to argue once, I believe, that implying
> Lyman break gave Swift spectral redshift capabilities.
> To start with thats NOT a spectral redshift, ...

Craig...
That is false.  See "photometric redshift."

Sean..
I think you deliberately misunderstand my statements.
By spectral redshift I mean a redshift derived from a
spectra observed and recorded through a collimator
dispersed through a diffraction grating or prism.
Does Swift have a collimator with a diffraction grating
where light in optical is dispersed into an image of a
spectrum that can then be either presented as a UV-R
colour continuum with dark and bright lines or a graph
of a hump shape with peaks and troughs? No.
Unfortunately in 2004 I incorrectly assumed it did and
thats why I make the prediction in that post.

> ... and
> secondly he forgets that my theory
> predicts that over time the intensity of brightness will
> fade first for the shorter wavelengths.

Craig..
Who cares?  The Lyman break is constant over time (at least time as
measured on human timescale).

Sean..
Obviously you care or you wouldnt keep posting to the
effect that you dont agree with any of my predictions,
like the one above.The problem you have is that you
saying  " the lyman break is constant over time " does
not alter the fact that the observed brightness always
fades in earlier wavelengths first. And in longer
wavelengths later , proportional to the length of the
observed wavelength.
I predicted that before you had any Swift data
confirming this. In fact before Swift went up.
That you can use it to infer possible redshift doesnt
alter the fact that I can use it to confirm
that lightspeed is not constant for the observor. The
difference between you and me is that I predicted it
before it was observed and you used the data after it
was observed to support beamed theory.
Dont forget too that in every grb observed the data
will never contradict my predictions, whereas in many
grbs there are many contradictions in inferred redshift
using your method. Including a recent swift one ..I
notice you conveniently deleted my example of
grb060206 gcn 4703. Is it a z=4.01, z=2.1 or z=1.4?
...




- Hide quoted text -
- Show quoted text -

> And just in case you have a problem understanding that
> I predicted no redshift from SWIFT specifically heres a
> bit of an explanation to help you understand the
> science behind my theory.

> I have clearly argued in 2004, *before then*,.. and
> after, that the usual approach of ground based
> telescopes to measure redshift of grb`s (like power
> law smoothing ) is an unnacceptable method of measuring
> grbs as far as ascribing a grb a fixed distance.
> The reason why I specifically made that claim that you
> misquote from  2004 vis a vis redshifts was exactly
> because I didnt accept at the time the validity of
> ground based spectra of purported grb OT`s and I
> felt the only way to supply any other countermanding
> evidence to support my claim was to rely on upcoming
> space based spectra from Swift. Unfortunately Swift
> doesnt supply any in optical. I was hoping it would.


Craig...
Your hopes are irrelevant.  Swift is almost always able to identify
the position of the afterglow counterpart very precisely, via its
sensitive X-ray Telescope.  There is no ambiguity when ground-based
observers identify the corresponding optical transient, or find its
redshift.  So whether you "accept ... the validity of ground based
spectra of purported GRB OT's" or not is irrelevant.  GRBs are indeed
very often at high redshift (Swift-detected GRBs especially so).


Sean..First of all did I say above or elsewhere that Swift
cant identify the location of the burst in X ray? No.
Never have I questioned Swifts locating abilities.And
 you will be unable to supply a quote where I say
that Swift Xrt cannot locate bursts.
The truth is that not only do your methods have a
patchy and contradictory history as I ve noted before
but your assumption that a lymann break being present
where there is no observation in Uv or V  is bad
science. Maybe the OT in those bands was below
threshold. Ever thought about that? They could have
faded earlier in shorter wavelengths to below
threshold and you missed them, like I always predicted.
In fact that possibility is supported by all the
evidence that afterglows in optical fade later in
longer wavelengths in all grbs. Not just 060218.
Look at your data. You cant deny that its observed
that the OT  always falls below threshold in shorter
wavelengths first. On pure impartial asessment of
evidence does that imply that anything `not seen`
or in other words `below` threshold doesnt exist?
Thats what you`re saying and thats creationism.
Just because people couldnt see america in 1400 AD
didnt definitely confirm it didnt exist. Good thing
Columbus didnt work for NASA

> In fact I believe you *can* see examples in the grb
> databases that show contradictions in redshifts for
> the same bursts. Or redshift measurements that
> contradict observed V-R magnitudes. Etc. For instance
> grb 060218 has some contradictory redshift conclusions
> from observed data-measured redshift of supposed host
> galaxy. See gcn 4790 & 4792 & 4805. Even 4809 although
> purporting to confirm an extragalactic source doesnt
> quite get around to admitting that new lines , not
> reflecting z=0.33 are showing up. They are unable to
> explain these , so invoke an SN!

Craig..
Really?  So it has a supernova-like spectrum, has a supernova-like
light curve... pretty good evidence to call it a supernova!  I note
that none of the GCNs you mention suggest anything other than z=0.033.


Sean..4790 says "However, we do not find evidence of under-
lying extended emission in our K'-band frame (0".7 seeing).
Together with the fact that the colour index of the
source is J-K = 0, unlike GRB afterglow colours
(see fig. 2 of Gorosabel et al. 2002, A&A 384, 11),
it clearly favours a high-energy transient in our
Galaxy."...Isnt that at odds with z=0.033?

4792 says.."This confirms the low-redshift, extragalactic
nature of this unusual GRB."... This is 0.033 yes, but
clearly contradicts gcn 4790 above

4805 says.."We also draw attention to the chromatic nature
of the Swift light curves.
The BAT emission peaked substantially earlier than the
XRT emission, which preceded the UVOT emission peak.
Although the low luminosity inferred from the low-z might
suggest a highly off-axis viewing angle for this burst,
an off-axis burst should show achromatic emission
variation, which is not seen here (see predictions by
Kumar, P. & Granot, J.
2003, ApJ, 591, 1075, for example.)"
So yes here even your team say z= 0.033 But note the
use of `probable`. I know why your team used probable
z=0.033 . Its because if 060218 cant be explained by your
team as a grb because an important observation doesnt
fit your model then it follows that it isnt a confirmed
grb or grbSN. And in that case it could be anything
including a closer galactic x ray transient . In
which case *you will* have to admit later that it couldnt
have been 0.033!

Regarding spectra. The paper says that its rise in
V was faster than expected for a SN and faster to decay.
I think they had to stretch it by something like 1.5 (!)
to make it fit any comparable known SN V band lightcurve.
THats a huge fiddle and not good science. They even admit
its unusual data and say its the fastest risetime on
record. Sounds like shaky evidence and revisionism to me.
A 150% stretch to make the lightcurve fit ! Who are they
trying to kid . Themselves obviously.. Furthermore trying
to fit all the data to a grb/SN event is really where the
`proof` gets even shakier as the researchers admit that if
this were a grbSN it was too luminous and needs further
study to double check other factors.
And finally , *you* cant just cherry pick one part of a
burst and say yes heres the proof its an SN. You have to
do what my theory does so well which is fit *all* the
evidence to the theory. Without fiddling the data grossly.
And this is exactly what beamed theory cant do for 060218.
Because ground based spectra or photometric, it cannot be
explained nor was predicted by beamed theory as an off
axis burst due to the chromatic nature of the afterglow.
So if its not explainable by you as an off axis grb but
it has to be one to explain the slow wavelength
evolution then you cannot say that this is a grb using
the beamed model. In which case it cant be a beamed grb SN.
And finally regarding the spectra. Yes Ive seen the paper
with some spectral results that sort of fit but not clearly
enough in my opinion. I accept that the evidence in these
so called spectral eviolutions can be made to look like a
SN. But dont forget I predict the same spectral
observations . Look at my website page two, graph of
spectral fit . There for years.I always argued that
ground based bursts observations would essentially be the
incoming blackbody spectrum  rapidly
redshifting and contaminated by the solar ISM. In other
words I always predict that the grb spectra would resemble
the solar spectra. And like any other grb does so does
060218. One can fit the main broad features of the
evolving observed spectra to a solar spectra as well
as one can to a real SN spectra. And the evolution to
redder end is explained by my theory as always, by my
prediction that the OT always reddens over time.
 So combine the solar spectra with a
reddening grb source in my theory gives as good a
fit to the evolving grb spectra as you get to a SN.
So my theory can explain your ground based spectral
results as being local contamination rather than real
redshift distance  *and* all the other observations
that your theory cant. Including your unscientific
use of power law smoothing which Stanek of course
has confirmed as being unsuitable and which I always
predicted as being unsuitable and which you always
unscientifically touted as being suitable.
So contrary to your above claims 060218 is anything
but proof of beamed theory. And the mushy soup paper
by Modjaz et al only highlites the fiddles and sloppy
theory that beamed theory employs to justify among
other things , apparent redshifts of grb`s
Craig..
I also note that you are cherry-picking a particularly peculiar burst
(see my previous post).  99.5% of bursts are not like 060218, so it is
dubious to draw any general conclusions from it.

Sean..I dont say that 060218 is the only burst that fits my
theory
In that post I explain how 060218 can be
*explained* by my theory and not by yours. But
I dont cherry pick grbs like you do. Name any grb
and I will show that all its observations fit all my
predictions. Unlike beamed theory which  very
frequently can only explain some of the observed
phenomena. In other words not only does beamed
theory cherry pick convenient grbs and avoid
the ones that dont fit, it also cherry picks only
some of the data from within each grb and leaves the
bits it cant explain . Like 060218, but there are
many others and you know that.



> But note that with
> gcn 4846 there is a sudden lack of interest in observing
> this grb . Why? Is it because it doesnt make sense under
> beamed theory ...

Craig...
I call BS.  In fact there have been many GCN observing reports since
#4846 (see GCNs 4847, 4853, 4863, 4866, 4898, 4899, and 4900).  It's
quite likely that observers are focussing on writing their papers.
And in fact, several papers have already appeared on the preprint
servers (Sollerman et al, astro-ph/0603495; Modjaz et al
astro-ph/0603377).  Your "conspiracy theory" is unfounded.


Sean...
Yes, I have read Modjaz et al. It clearly concludes that
it clearly cant conclude.
Another vague statement it makes is that the supposed
host galaxy doesnt seem to contribute to the observed
continuum except where the afterglow has faded significantly
in blue. Do all SN not show host galaxy contamination
except in very blue parts of the spectrum?If this isnt
the norm then surely that supports the conclusion
I always predict which is the observed afterglow never
ever had its source in the supposed host galaxy. 
Sean


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