Yes I did
Data from last night
V= 4.937
B = 5.028
This is a slight drom in V and less of a drop in B since my last measurement on 5/1/14
The spectra shows an identical relative Ha emission but an increas in the blue continuum.
When I graph the flux calibrated data, there has been a drop in the absolute height of Ha but an increas in the blue continuum. This fits with the reduction of B-V my photometry displays.
Cheers
Terry
Good stuff Terry.
The previous night (Friday) I had V 4.95 and B 5.04.
Looking at the spectra overall for this nova there's an interesting fluctuation in the level of the blue continuum. I at first thought I was being sloppy with the instrument response correction, but I'm sure it's real. I'm not quite sure how it lines up against the magnitude fluctuations.
Seems to be a fluctuation in how much "fireball" we see vs how much extended and increasingly nebulous ejecta.
The previous night (Friday) I had V 4.95 and B 5.04.
Looking at the spectra overall for this nova there's an interesting fluctuation in the level of the blue continuum. I at first thought I was being sloppy with the instrument response correction, but I'm sure it's real. I'm not quite sure how it lines up against the magnitude fluctuations.
Seems to be a fluctuation in how much "fireball" we see vs how much extended and increasingly nebulous ejecta.
I agree Jon.
I was worried that there was something wrong with my instrument response but I checked it carefully using various processing methods. I kept coming up with the same response so I ageee that it seems to be real.
It will be much easier in a month when it rises at a better time.
Terry
Hi all - I actually got up early this morning rather than staying up late and the sky was absolutely brilliant! First time I've been really dark adapted for this nova since early Dec and it was still a little gem naked-eye, amazing! Then I turned the camera on and that bit was over sadly...
Anyway, first time I've taken a spectrum of it since 6 Jan (why bother when you guys are on a roll!) but I notice some big changes since then. Most obvious is the continued growth in strength of the H-gamma line. I now have a long series of low-res spectra of this nova and when I first started shooting the violet end of the spectrum was barely registering and the H-gamma line was invisible or barely visible.
Second is the deepening of the hydrogen absorption lines (P-Cyg profile).
Last night's spectrum is on top, 6th below. Taken with SA100 grating, both sets with Canon 650D, 200mm lens, 12-sec exposures, same ISO & F/stop.
Nice, Rob. That's now three of us who have recorded the brightening of the blue end of the spectrum.
I have had the opposite experience to you - this is the first spectrum I stayed up for, as opposed to setting the 3am alarm (which my wife has attempted to veto). A bit less detail because airmass was about 2.2 when I took this.
Still, more civilised :-)
Oops, just realised the title on the image is wrong. It's 12/1/2013 13:30
Nice work Jon! I notice little 'steps' that appear to exist between the H-alpha and H-beta absorption and emission lines. Any handle on what they mean, if anything?
Managed to collect some data around Ha and Hb.
The P-Cyg profiles have changed (evidence of a third dip???)
and the Fe lines are getting "untidy"
I'll upload ASAP.
The attached profiles around Ha and Hb show some interesting features - there appears to be the start of absorption in the lines, and the P-Cyg is getting more complex.
The attached profiles around Ha and Hb show some interesting features - there appears to be the start of absorption in the lines, and the P-Cyg is getting more complex.
Excellent Ken! Clearly shows the little 'steps' between the absorption & emission lines.
Rob,
You did well to pick that level of detail!
I've cut your jpg, converted to Luminence and exported to VSpec.
The attached profile (roughly calibrated) shows what's there.....
(We can get a better result from a cropped RAW ;-) )
Thanks Ken - yes, I have RAWs, I've just got to get around to forwarding them! There is a small computer issue that's been holding me back, although in truth that's probably just an excuse! My old version of PS won't handle RAWs and my desktop's disc-drive has ceased to function as far as loading camera software goes. I was going to do it on the laptop but blah, blah, blah...
The attached profiles around Ha and Hb show some interesting features - there appears to be the start of absorption in the lines, and the P-Cyg is getting more complex.
Fantastic Ken.
Showing a further increase in velocity of the absorption features. I'm not sure if it's the same phenomenon, but a very similar progression is shown in Steve Shore's 'Spectroscopy of Novae - A Users Manual', Figures 4 and 5 (pages 8 & 9) http://arxiv.org/abs/1211.3176
Unfortunately I can't pretend to be able to decipher the accompanying text.
Showing a further increase in velocity of the absorption features. I'm not sure if it's the same phenomenon, but a very similar progression is shown in Steve Shore's 'Spectroscopy of Novae - A Users Manual', Figures 4 and 5 (pages 8 & 9) http://arxiv.org/abs/1211.3176
Unfortunately I can't pretend to be able to decipher the accompanying text.
It does have moments of complete incomprehensibility to those of us who haven't got all the quantum energy state transitions, along with accompanying resonances (whatever they are) committed to memory!
It does have moments of complete incomprehensibility to those of us who haven't got all the quantum energy state transitions, along with accompanying resonances (whatever they are) committed to memory!
I think a resonance transition is just when a photon of a particular frequency is absorbed and then one of the same frequency is emitted as the electron drops back down to it's previous energy level.
I think a resonance transition is just when a photon of a particular frequency is absorbed and then one of the same frequency is emitted as the electron drops back down to it's previous energy level.
Ah, is that all? That's simple enough. When he writes something like "During the cooling stage, when the optical spectrum is strengthening, the ultraviolet – the site of the resonance transitions of the same iron peak ions that dominate the optical spectrum – suddenly becomes optically thick" I thought there was some obscure quantum relationship between UV iron ions and the FeII we are seeing in the visual.
But now I reread it, all he means is that in the UV, the Fe is being bombarded by UV wavelengths, so absorbing and re-emitting individual photons (resonance) at those same wavelengths. But up in the optical spectrum (e.g. at 5018 and similar) those same ions are emitting photons through recombination, as they absorb an electron and emit a photon and move from FeII to FeI), or through transition, as they lose a photon as they drop down an energy state.
That makes sense, as the wavelengths being pumped out by the WD are strongest at the high-energy wavelengths, UV and lower, yes?
Numerous celestial bodies managed to align themselves for me two nights ago and I got a second look at the nova.
Timing meant I wasn't able to get up early, and I was playing with a new camera, but at the end of the session I decided to see what could be recorded.
Because it wasn't planned and involves a different camera, I've ended up with 15 Angstroms per pixel instead of the usual 9.5-9.7.
Anyway, excuses aside, this was 10:40 pm Sydney time on 14th January.
Most of the features seem to line up quite well with Jon's spectrum and as a result I've taken his identification.
I've also included a comparison with my earlier spectrum.
Good to see more data being collected.
The red response looks a bit strange...could be 2nd order contamination or camera response.
Which camera and set-up did you use?
