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budhies:telecon_21_03_2012

Things to discuss during the Telecon:

  1. 1 main result for letter on A2192
    • The important result so far is that HI and [OII] have common behaviour in A2192_1a and _1d, and in A2192_b and_c.
    • This is still crude in the sense that we don't have HI deficiencies or SF deficiencies, but taking this at face value, we can focus on the clear trends we see on “bound structures” (wehat I called “presence of a halo” in the paper) vs non bound ones!
    • We already saw lower EW[OII] for example in the clusters, and with Maria's SFRs (See Fig 1) we are starting to look at the SFR-M relation, but what could really help us getting an answer would be the HI-deficiencies.
  2. HI deficiencies: important to see if there is further evidence of deficiency in the “clusters”
    • How easy is it to do? Method can be that of Aeree's 2009 paper (sec 5.5). As Marc pointed out to me, there is the problem of not having reliable morphologies to correct for variations in the surface density with morphology, but I think we can live with averaging on the morphologies and having greater uncertainties. What I don't know is how easy is it to calculate this SIGMA_HI (i.e. Hi surface density within the optical disk)? Is it easy? any volunteers?
  3. SFRs:
    • Maria has UV SFRs (available on the wiki)!! she (and David) used dust-corrections following Salim et al 2007 . Remaning questions: Wich IMF was used? was it Chabrier (2003)? Yes, it was Chabrier (María). I used Kroupa IMF for the stellar masses… Moreover, there is the paper by Elbaz et al 2007 (see fig 18) that has a SFR-M relation for blue SDSS galaxies at 0.015<z<0.1 that could serve as a comparisson, and he uses a Salpeter IMF. Basically all the IMFs are different, so we need to correct for that!. Finally, we can also compare with AEGIS field galaxies (see Noeske et al. (2007,a,b)). I just got the data and made a quick plot (see second Figure 1).
    • Ryan: any news on the 24 micron SFRs?
  4. X rays: Thanks to Jacqueline we now know that the X-ray centre of A2192 coincides with the “centre” of A2192_1a! (Fig 2)
  5. A963:
    • On the blue fraction: See Figure(s) 3
  6. The TFR

Fig. 1: UV_SFR vs M_stellar for A2192 structures

AEGIS SFR - M* (big symbols correspond to z~0.2):

ir = galaxies with 24um detections (>60 uJy) - SFR derived from SF(24um) + SFR(emission lin es, uncorr. f. extinction)

blue = alaxies with no 24um emission (or <60uJy), but blue optical colors and emission lines. SFR derived from extinction-corrected emission lines, using an average DEEP2 line ratio as quoted in the first 2007 letter (not the M_H dependent line ratios given in Weiner et al. 2007 because these gave me larger SFR than 24um + emission lines).


Fig 2: X-rays

First Figure courtesy of Eli Rykoff (via Jacqueline)

I quote from his email: As for Abell 2192, this is a bit confusing. The redshift listed in SIMBAD is 0.03, which is clearly not correct. That said, the richness isn't that impressive.

I've attached a couple of SDSS images of the two clusters, overlaid with ROSAT contours (in green). [Ignore what's labeled as “R200”] ONe is clearly a nice X-ray cluster, the other has a bit of X-ray emission. However, there is a source in the ROSAT Bright Source Catalog coincident with the cluster center.

This corresponds to a LX~7e43 h_100^-2 erg/s, as I said.

And that's about all I know. A literature search is certainly complicated by the misidentification in SIMBAD.


Fig 3: On the blue fractions in A963

Now in the next plot I separate by structure:

I measured blue fractions in the red and green points and got:

f_B (A2192_1 / red) = 43.4%
f_B (A2192_2 /green) = 52.6%
f_B (A2192_1 + A2192_2 / green and red) = 45.6%

blue= Lavery & Henry; red= ours; blac circles = HI detections

Note that NONE of the LH galaxies are HI detected

See the z histogram of the plotted points here:



Large Scale Structure over 5 degree (50 Mpc) scales (by M. Yun)

Just to follow-up on what I said earlier at the telecon, here are the plots I mentioned. These are about 1000 galaxies each in the directions of two target clusters, nearly all with SDSS specz. The “big” magenta circle in the middle is about 1 degree in diameter, similar to the circle in Marc's 2007 paper. Different colors represent different redshifts, obviously.

* A963: blue (0.14<z<0.18), green (0.18 <z<0.23), red (0.23<z<0.28)

* A2192: blue (0.12<z<0.15), cyan (0.15<z<0.17), green (0.17<z<0.21), and red (0.21<z<0.24)

We are beginning to bump into the SDSS redshift limit here, so you see fewer galaxies at higher-z bins, but you can see the LSS across both of these fields. As expected, A963 is clearly a local density peak, but A2192 isn't so obvious. It is part of a fairly substantial filament at z=0.18, but through a void at z=0.14.


M_HI / M* vs. M* for A2192's structures (Yara)

All the blue points are field
clusters that are not A2192_1 are magenta
A2192_1a =red
A2192_1b =grey
A2192_1c =turquoise
A2192_1d =yellow

Ryan's SFR vs. M* for A2192's structures (Yara)

budhies/telecon_21_03_2012.txt · Last modified: 2012/03/22 11:22 by 127.0.0.1