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15367
Re: Skewness ... Hi Peter, No, I understood completely. You said "The first order moment basically determines the median wavelength. Rather than associating the line
Stan Gorodenski
3:49 PM
#15367

15366
Re: Skewness Hi Stan. It seems the meaning was unclear with regard to my statement about the 1st order moment. The 1st order moment gives the mean value of the distributed
pwhz1956
12:16 PM
#15366

15365
Re: Skewness I just looked at the paper. The math is way beyond me. Stan
Stan Gorodenski
11:49 AM
#15365

15364
Re: question for anyone on this group Plasma balls available in the US from this good vendor: http://www.arborsci.com/7-plasma-globe http://www.arborsci.com/7-plasma-globe
tomrspec
11:38 AM
#15364

15363
Re: Skewness Hi Peter, I have been thinking about this and I am afraid I have to disagree with your statement that /"The first order moment basically determines the median
Stan Gorodenski
11:24 AM
#15363

15362
Re: Skewness Thanks for the good information, Peter. This might clear up some of the questions in my mind I have. Stan
Stan Gorodenski
9:14 AM
#15362

15361
Re: Skewness Hi Stan. I'm a newcomer to astronomical spectroscopy but, from what I have studied, it seems that dealing with asymmetrical lineshapes would be the norm rather
pwhz1956
8:38 AM
#15361

15360
Need of spectroscopy fo a new supernova discovery Hello, My PhD student, Damien TURPIN, has just discovered a new possible supernova in the Nothern hemisphere (in UGC 6483):
Alain Klotz
Dec 11
#15360

15359
Re: Skewness The wall hiding Vega would hide it parallel to the spinning axis, of course... On Wed, Dec 11, 2013 at 9:17 PM, Filipe Dias ... -- Fil.
Filipe Dias
Dec 11
#15359

15358
Re: Skewness If you have a star, assumed symmetrical, that is spinning and the amount of material coming towards the observer is different in intensity compared to the
Filipe Dias
Dec 11
#15358

15357
Re: Skewness Hi Stan, Leaving aside optical aberrations in the spectrograph and blending of lines, I suspect radial velocity variations within the object are probably the
Dec 11
#15357

15356
Re: Skewness Thanks, Benji. It appears, from what you said, there are processes that modify a line's wavelength in the sense of translating the line center. What I was
Stan Gorodenski
Dec 11
#15356

15355
Re: Skewness Hello Daniela, Line formation, as you said, comes from physic involved in star's photosphere and outer disc if it exists. Process are discribed by Quantic
B Mauclaire
Dec 11
#15355

15354
Re: Skewness I don't presume to be able to respond (very interested in what others will say) due to lack of understanding of all physical processes involved in the
daniela daniela
Dec 11
#15354

15353
Spectrohéliogrammes du 10 Décembre Bonjour à tous, Voici 4 spectrohéliogrammes pris le 10 Décembre en région parisienne au voisinage du méridien sur les raies H alpha, H beta,CaK3 et CaK1V.
Jean-Jacques POUPEAU
Dec 11
#15353

15352
Re: [astronomical_spectroscopy] Nova Centauri 2013 archive http://www.threehillsobservatory.co.uk/astro/stacking_FAQ/noise/stacking_noise.htm ... From: Robin Leadbeater To: spectro-l@yahoogroups.com Sent: Wednesday,
Dec 11
#15352

15351
Re: [astronomical_spectroscopy] Nova Centauri 2013 archive Hi Ken, Malc Adding or averaging using floating point average are both ok. The key is that you export in a 16 bit (or higher) format to preserve the total
Dec 11
#15351

15350
Re: [astronomical_spectroscopy] Nova Centauri 2013 archive By adding the signal before averaging you get a significant improvement in SNR...that's what it's all about. ... -- "Astronomical Spectroscopy - The Final
Ken Harrison
Dec 11
#15350

15349
Nova Centauri 2013 update - Dec 11 2013 V1369 Centauri = Nova Centauri 2013 = PNV J13544700-5909080 R.A. = 13h54m45s.34, Decl. = -59o09'04".2 (equinox 2000.0) First entries in the ARAS database ...
Malcolm Locke
Dec 10
#15349
This message has attachments
15348
Re: [astronomical_spectroscopy] Nova Centauri 2013 archive ... Hi Robin, It's a QHY5. I guess my question is whether the 8 bit capture is OK. I realise the data can be manipulated in various ways to fit into a 16 or
Malcolm Locke
Dec 10
#15348

15347
Skewness I have a question concerning a spectral line that has a skewed shape, i.e., the shapes on each side of a vertical line running through the peak intensity of
Stan Gorodenski
Dec 10
#15347

15346
Re: [astronomical_spectroscopy] Nova Centauri 2013 archive Hmmmm I've just been through a lengthy discussion (on SGL) where the "experts" demonstrated that averaging, rather than summing gives the same improved SNR and
Ken Harrison
Dec 10
#15346

15345
Re: [astronomical_spectroscopy] Nova Centauri 2013 archive Hi Malc, ... I don't recall what camera you have but I used a modified 8 bit webcam for several years doing photometry and spectroscopy. You can increase the
Dec 10
#15345

15344
Re: [astronomical_spectroscopy] Nova Centauri 2013 archive Ok for the 8-bits (we can transform from 8->16 bits). Spectroscopy is exigent about camera quality (low noise, high dynamic, linearity). Consider a good
Christian Buil
Dec 10
#15344

15343
Re: *** SPAM *** [spectro-l] Comet Lovejoy C/2013 R1 - Dec 7 Thanks Robin! Yes, it seems there is no evidence of Na doublet emission during my observed session (comet at 0.864 AU from the sun). I try to extract the
paolo_berardi
Dec 10
#15343

15342
Re: question for anyone on this group thank you so much , what an inventive idea. I will take a look at these! Ron D Ron DiIulio Sent from my iPhone ... thank you so much , what an inventive idea.
Ron Diiulio
Dec 10
#15342

15341
Re: question for anyone on this group Hi, I live in the UK and a web search yielded Plasma Ball lamps sold by Amazon for a few tens of pounds, luckily we had bought one for our son as a present
Ken Whight
Dec 10
#15341

15340
Re: Question re non-linear dispertion fits headers I have also encountered professional spectra which are not linearised and have the calibration coefficients included in the header. (Also ones where the
Dec 10
#15340

15339
Re: Question re non-linear dispertion fits headers Hello Malcom, You touched an important point. In order to be readable by other softwares, spectral pipelines do compute in memory non linear wavelength
B Mauclaire
Dec 10
#15339

15338
Re: question for anyone on this group Where are you and where do you buy your xenon plasma ball lamp 'W And cost jack 47'N 71 On 12/9/2013 5:40 PM, Ken Whight wrote: I've found that a xenon
jacot
Dec 10
#15338

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