Thursday, January 27, 2011


Read Kormendy et al. paper for quasar journal club, then missed the Skype session. Wrote up comments and emailed them around.

Individual Skype sessions with Ali Rafiee, Laura Chajet and Jesse Rogerson.

Copied all dereddened Hewett & Wild spectra (with their redshifts in the header) to my laptop. Started adopting spectro.boss SM file to work with those spectra.

Tuesday was mostly PHL 1811 analog selection: the sequel. Men it can be done. And we have more good candidates. But the SDSS blueshifts are not trustworthy for these extreme objects, so a visual inspection stage is still required.

Received Gemini GMOS pre-imaging data for the clone arc. To my chagrin, the rotation angle is not quite optimal. Will have to consider whether to request another pre-image at a slightly different rotation angle, probably after taking a stab at mask design [there's also the issue of how well a curved slit can be faked; may need to contact Gemini about testing beta software for curved slits].

General discussion with Paul Hewett about topics of mutual interest to work on.

Monday, January 24, 2011

3C 120 and the like, redux: Death of an HST Proposal?

Continuing the last post's discussion of studying the broad-emission-line profiles of objects with known inclinations: There are a handful of "radio-intermediate quasars" which appear to be intrinsically radio-quiet quasars whose radio flux is boosted by beaming. Such objects likely have a combination of jet speeds higher than average for RQQs and jet angles to the line of sight smaller than average for RQQs, but for any significant boosting factor, small inclination angles i<20 are needed to distinguish them from unbeamed RQQs, as seen in
Figure 13.9 here.

If such objects show disk-wind dominated BELR dynamics, they should have large C IV blueshifts relative to Mg II. But only 2 of 5 objects do:

3C 120 : redshift 104 +- 9 km/s
III Zw 2 : redshift 100 +- 100 km/s
PG 1309+355 : redshift 220 +- 10 km/s (slight uncertainty due to assoc. C IV abs.)
PG 2209+184 : blueshift 1000 +- 50 km/s
PG 1407+263 : blueshift 4430 +- 1340 km/s

So... unsurprisingly, things are more complex than simple inclination dependence of line profiles. Small inclinations and large blueshifts are not interchangeable.

So my enthusiasm for proposing for HST spectra of gamma-ray NLS1s has decreased. But not vanished - if the above objects' line profiles (and the optical line profiles of the gamma-ray loud NLS1s) can be understood as resulting from the combined effects of inclination, radio-loudness and Eddington ratio (e.g., intermediate or high L/Ledd may quench radio jets present at other L/Ledd values; Churazov et al. 2005MNRAS.363L..91C), then an HST proposal would be well-motivated.

Sunday, January 23, 2011

3C 120 and the like

Dereddened DR7 quasar spectra for Ali Rafiee.

Outlined steps to improve selection of PHL 1811 analogs.

Posted comments on a paper on shareflow.

Downloaded and coadded IUE spectra of 3C 120 as a test of what quasar spectra look like at 20.5+-1.8 degrees from face-on (as determined by the radio jet orientation; Jorstad et al 2005). C IV peak is redshifted by ~104 km/s relative to Mg II peak (assuming 1:1 doublet ratios in both lines). Naively I would have expected C IV to be blueshifted. (Mg II is blueshifted by 261 km/s from NED redshift, but within the uncertainties/systematics all three redshifts are probably consistent.) So it may be that in radio-loud quasars the disk wind is suppressed, which means that studying the emission-line profiles of RLQs where you know the inclination doesn't tell you anything about RQQs at similar inclinations. Problematic for my idea of an HST proposal for gamma-ray loud NLS1s. But I can still try and see what disk wind parameters at inclination i=20 do and do not match the 3C 120 C IV line profile; the results may be interesting.

Another approach to studying the line profiles of objects with known inclinations would be to turn to the handful of radio-quiet/intermediate quasars known or thought to have superluminal motion. Such objects may still show disk-wind dominated dynamics, and their beamed nature means they're likely close to the line of sight.* There are 4 such RIQs (beamed RQQs), the 1st 2 of which have confirmed superluminal motions:
PG 1407+263, Blundell et al. 2003ApJ...591L.103B [known to have large blueshifts];
III Zw 2, 1996ApJ...473L..13F & 2000A&A...357L..45B (though i<41 there was overruled by 2005 paper) & 2005A&A...435..497B;
PG 1309+355, 1996ApJ...473L..13F;
PG 2209+184, 1996ApJ...473L..13F.
There is HST y/o IUE data on all of these, at which I'm starting to take a look.

* Caveat: need to keep in mind that beaming depends very much on jet velocity as well as angle to the line of sight. It may be that RIQs are the subpopulation of RQQs with the highest jet speeds, rather than the subpopulation seen at very small angles to the jet.

Friday, January 21, 2011

Three Days

Wednesday was quasar journal club. Worked a bit more on plotting results of Davis & Agol inhomogeneous accretion disk, but haven't finished it yet.

Thursday was colloquium by Vivienne Wild, and colloquium dinner, and some science discussion, and sorting old science/project notes of my own.

Friday I finished assembling information on duplicate spectra of SDSS DR7 quasars for Ali Rafiee.

Tuesday, January 18, 2011

Two Days

Updated installations of skycat, GEMINI and other IRAF packages, plus APT and gmmps. Got copy/paste working between terminal/xterm, and xterm/xgterm, but not between terminal/xgterm.

Obtained and checked HST imaging data to help in Clone lens mask design.

Skype chats with students L. Chajet and J. Rogerson.

Some writeups/postings on papers for Shareflow.

Finished writing sm code for size of Dexter & Agol inhomogeneous accretion disk; that is, radius which encloses X% of the light at wavelength Y.

Friday, January 14, 2011

Friday Fun

Gave presentation to ~9 IoA members interested in extragalactic astronomy. Covered Jesse Rogerson's Mg II absorber work, our Gemini proposal, and the disappearing FeLoBAL troughs in FBQS J1408+3054.

Read papers on microlensing studies of quasar BELRs, among other topics.

Thursday, January 13, 2011

Thursday the 13th!

Finished my end of Gemini Phase II; turns out I need to get an OK for adding an hour angle constraint, so I await word on that. One lesson learned is that there are lots of complexities to using curved slits at fixed angles on the sky to get spectra of gravitationally lensed arcs; IFUs on 30-meter class telescopes will make these observations much simpler someday [more compact lenses can be done now with IFUs on 8-meter class telescopes, but aren't as useful for the application I have in mind].

Did a 10-15 minute interview for an Institute of Astronomy podcast that should appear next month.

Worked on my informal presentation for tomorrow's extragalactic gathering.

Wed. Jan. 12

Did a bit more work on Gemini Phase II, but primarily worked on PHL 1811 analogs, mostly on figuring out how many narrow-line C IV absorbers they have as compared to expectations for quasars in general.

Tuesday, January 11, 2011

Blogging Anew!

First real day back at work (now at the Institute of Astronomy in Cambridge, UK).
Sent off reference letters for former student & current postdoc Ali Rafiee.
Worked on Gemini Phase II planning for spectroscopy of a giant arc.