Five new lichen species (Ascomycota) and a new record from southern New South Wales, Australia

Five lichen species (Ascomycota) are described as new from rocks in coastal and tableland localities of southern New South Wales: Catillaria gerroana P.M.McCarthy & Elix (Catillariaceae), Fellhanera robusta P.M.McCarthy & Elix (Pilocarpaceae), Menegazzia fortuita Elix & P.M.McCarthy (Parmeliaceae), Ramboldia curvispora P.M.McCarthy & Elix (Lecanoraceae) and Sarcogyne maritima P.M.McCarthy & Elix (Acarosporaceae). Arthonia lapidicola (Taylor) Branth & Rostrup (Arthoniaceae) is reported for the first time from Australia

Very Red and Extremely Red Galaxies in the Fields of z ~ 1.5 Radio-Loud Quasars

We previously identified an excess of mostly red galaxies around 31 RLQs at z=1-2. These fields have an ERO (extremely red object, R-K>6) density 2.7 times higher than the field. Assuming the EROs are passively evolved galaxies at the quasar redshifts, they have characteristic luminosities of only ~L^*. We also present new observations of four z~1.54 RLQ fields: (1) Wide-field J & Ks data confirm an Abell richness ~2 excess within 140" of Q0835+580 but an excess only within 50" of Q1126+101. (2) In 3 fields we present deep narrow-band redshifted H-alpha observations. We detect five candidate galaxies at the quasar redshifts, a surface density 2.5x higher than the field. (3) SCUBA sub-mm observations of 3 fields detect 2 quasars and 2 galaxies with SEDs best fit as highly reddened galaxies at the quasar z. (4) H-band adaptive optics (AO) imaging is used to estimate redshifts for 2 red, bulge-dominated galaxies using the Kormendy relation. Both have structural redshifts foreground to the quasar, but these are not confirmed by photometric redshifts, possibly because their optical photometry is corrupted by scattered light from the AO guidestar. (5) We use quantitative SED fits to constrain the photometric redshifts z_ph for some galaxies. Most galaxies near Q0835+580 are consistent with being at its redshift, including a candidate very old passively evolving galaxy. Many very & extremely red objects have z_ph z_q, and dust reddening is required to fit most of them, including many objects whose fits also require relatively old stellar populations. Large reddenings of E(B-V)~0.6 are required to fit four J-K selected EROs, though all but one of them have best-fit z_ph>z_q. These objects may represent a population of dusty high-z galaxies underrepresented in optically selected samples. (Abridged)Comment: Missing object 1126.424 added to Table 4; title changed to save people the apparent trouble of reading the abstract. 38 pages, 16 figures, 2 in color; all-PostScript figure version available from http://astro.princeton.edu/~pathall/tp3.ps.g

Star Formation in Emission-Line Galaxies Between Redshifts of 0.8 and 1.6

Optical spectra of 14 emission-line galaxies representative of the 1999 NICMOS parallel grism Ha survey of McCarthy et al. are presented. Of the 14, 9 have emission lines confirming the redshifts found in the grism survey. The higher resolution of our optical spectra improves the redshift accuracy by a factor of 5. The [O II]/Ha values of our sample are found to be more than two times lower than expected from Jansen et al. This [O II]/Ha ratio discrepancy is most likely explained by additional reddening in our Ha-selected sample [on average, as much as an extra E(B-V) = 0.6], as well as to a possible stronger dependence of the [O II]/Ha ratio on galaxy luminosity than is found in local galaxies. The result is that star formation rates (SFRs) calculated from [O II]3727 emission, uncorrected for extinction, are found to be on average 4 +/- 2 times lower than the SFRs calculated from Ha emission. Classification of emission-line galaxies as starburst or Seyfert galaxies based on comparison of the ratios [O II]/Hb and [Ne III]3869/Hb is discussed. New Seyfert 1 diagnostics using the Ha line luminosity, H-band absolute magnitude, and Ha equivalent widths are also presented. One galaxy is classified as a Seyfert 1 based on its broad emission lines, implying a comoving number density for Seyfert 1s of 2.5{+5.9, -2.1} times 10^{-5} Mpc^{-3}. This commoving number density is a factor of 2.4{+5.5,-2.0} times higher than estimated by other surveys.Comment: 51 pages, 18 figures; Accepted for publication in the Astrophysical Journal; Revised version with minor changes and an additional reference which gives further support to our conclusion

Extragalactic Fields Optimized for Adaptive Optics

In this paper we present the coordinates of 67 55' x 55' patches of sky which have the rare combination of both high stellar surface density (>0.5 arcmin^{-2} with 13<R<16.5 mag) and low extinction (E(B-V)<0.1). These fields are ideal for adaptive-optics based follow-up of extragalactic targets. One region of sky, situated near Baade's Window, contains most of the patches we have identified. Our optimal field, centered at RA: 7h24m3s, Dec: -1deg27'15", has an additional advantage of being accessible from both hemispheres. We propose a figure of merit for quantifying real-world adaptive optics performance, and use this to analyze the performance of multi-conjugate adaptive optics in these fields. We also compare our results to those that would be obtained in existing deep fields. In some cases adaptive optics observations undertaken in the fields given in this paper would be orders of magnitude more efficient than equivalent observations undertaken in existing deep fields.Comment: 28 pages, 15 figures, 1 table; accepted for publication in PAS

Probing Very Bright End of Galaxy Luminosity Function at z >~ 7 Using Hubble Space Telescope Pure Parallel Observations

We report the first results from the Hubble Infrared Pure Parallel Imaging Extragalactic Survey, which utilizes the pure parallel orbits of the Hubble Space Telescope to do deep imaging along a large number of random sightlines. To date, our analysis includes 26 widely separated fields observed by the Wide Field Camera 3, which amounts to 122.8 sq.arcmin in total area. We have found three bright Y098-dropouts, which are candidate galaxies at z >~ 7.4. One of these objects shows an indication of peculiar variability and its nature is uncertain. The other two objects are among the brightest candidate galaxies at these redshifts known to date L>2L*. Such very luminous objects could be the progenitors of the high-mass Lyman break galaxis (LBGs) observed at lower redshifts (up to z~5). While our sample is still limited in size, it is much less subject to the uncertainty caused by "cosmic variance" than other samples because it is derived using fields along many random sightlines. We find that the existence of the brightest candidate at z~7.4 is not well explained by the current luminosity function (LF) estimates at z~8. However, its inferred surface density could be explained by the prediction from the LFs at z~7 if it belongs to the high-redshift tail of the galaxy population at z~7.Comment: ApJL in press (accepted Dec. 27, 2010); minor corrections and one figure added to address referee's comment

Demonstrating Diversity in Star Formation Histories with the CSI Survey

We present coarse but robust star formation histories (SFHs) derived from spectro-photometric data of the Carnegie-Spitzer-IMACS Survey, for 22,494 galaxies at 0.3<z<0.9 with stellar masses of 10^9 Msun to 10^12 Msun. Our study moves beyond "average" SFHs and distribution functions of specific star formation rates (sSFRs) to individually measured SFHs for tens of thousands of galaxies. By comparing star formation rates (SFRs) with timescales of 10^10, 10^9, and 10^8 years, we find a wide diversity of SFHs: 'old galaxies' that formed most or all of their stars early; galaxies that formed stars with declining or constant SFRs over a Hubble time, and genuinely 'young galaxies' that formed most of their stars since z=1. This sequence is one of decreasing stellar mass, but, remarkably, each type is found over a mass range of a factor of 10. Conversely, galaxies at any given mass follow a wide range of SFHs, leading us to conclude that: (1) halo mass does not uniquely determine SFHs; (2) there is no 'typical' evolutionary track; and (3) "abundance matching" has limitations as a tool for inferring physics. Our observations imply that SFHs are set at an early epoch, and that--for most galaxies--the decline and cessation of star formation occurs over a Hubble-time, without distinct "quenching" events. SFH diversity is inconsistent with models where galaxy mass, at any given epoch, grows simply along relations between SFR and stellar mass, but is consistent with a 2-parameter lognormal form, lending credence to this model from a new and independent perspective.Comment: 17 pages, 10 figures; accepted by ApJ; version 2 - no substantive changes; clarifications and correction