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Publications and source records attributed to Eisenhardt, Peter.
In the published version of this paper, Roberto Assef was mistakenly affiliated with the Division of Astronomy and Astrophysics at the University of California, Los Angeles. This is incorrect. Dr. Assef's affiliation correctly appears in this erratum as the Nucleo de Astronomıa de la Facultad de Ingenierıa, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile. IOP Publishing sincerely regrets this error.
On behalf of the WISE Science team, we present the discovery of a class of distant dust-enshrouded galaxies with extremely high luminosity. These galaxies are selected to have extreme red colors in the mid-IR using NASA's Wide-field Infrared Survey Explorer (WISE). They are faint in the optical and near-IR, predominantly at zeta = 2-4, and with IR luminosity > 10(exp 13) Solar Luminosity, making them Hyper-Luminous Infrared Galaxies (HyLIRGs). SEDs incorporating the WISE, Spitzer, and Herschel PACS and SPIRE photometry indicate hot dust dominates the bolometric luminosity, presumably powered by AGN. Preliminary multi-wavelength follow-up suggests that they are different from normal populations in the local M-sigma relation. Their low source density implies that these objects are either intrinsically rare, or a short-lived phase in a more numerous population. If the latter is the case, these hot, dust-enshrouded galaxies may be an early stage in the interplay between AGN and galaxies.
We present WISE All-Sky mid-infrared (IR) survey detections of 55 % (17/31) of the known QSOs at z greater than 6 from a range of surveys: the SDSS, the CFHT-LS, FIRST, Spitzer and UK1DSS. The WISE catalog thus provides a substantial increase in tiie quantity of IR data available for these sources: 17 are detected in the WISE Wl (3.4 micrometer) band, 16 in W2 (4.6 micrometers), 3 in W3 (12 micrometers) and 0 in W4 (22micrometers). This is particularly important with Spitzer in its warm-mission phase and no faint follow-up capability at wavelengths longwards of 5 micrometers until the launch of JWST. WISE thus provides a useful tool for understanding QSOs found in forthcoming large-area optical/IR sky surveys, using PanSTARRS, SkyMapper, VISTA, DES and LSST. The rest-UV properties of the WISE-detected and the WISE-non-detected samples differ: the detections have brighter i/z-band magnitudes and redder rest-UV colors. This suggests thai a more aggressive hunt for very-high-redshift QSOs, by combining WISE Wl and W2 data with red observed optical colors could be effective at least, for a subset of dusty candidate QSOs. Stacking the WISE images of the WISE-non-detected QSOs indicates that they are on average significantly fainter than the WISE-detccted examples, and are thus not narrowly missing detection in the WISE catalog. The WISE-catalog detection of three of our sample in the W3 band indicates that their mid-ID flux can be detected individually, although there is no stacked W3 detection of sources detected in Wl but not. W3. Stacking analyses of WISE data for large AGN samples will be a useful tool, and high-redshifl. QSOs of all types will be easy targets for JWST.
By combining data from the NASA Wide-field Infrared Survey Explorer (WISE) mission with optical spectroscopy from the W. M. Keck telescope, we discover a mid-IR color criterion that yields a 78% success rate in identifying rare, typically radio-quiet, 1.6 approx. < z approx. < 4.6 dusty Ly-alpha emitters (LAEs). Of these, at least 37% have emission extended on scales of 30-100 kpc and are considered Ly-alpha "blobs" (LABs). The objects have a surface density of only approx.. 0.1 deg(exp -2), making them rare enough that they have been largely missed in deep, small area surveys. We measured spectroscopic redshifts for 92 of these galaxies, and find that the LAEs (LABs) have a median redshift of 2.3 (2.5). The WISE photometry coupled with data from Herschel (Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA) reveals that these galaxies are in the Hyper Luminous IR galaxy regime (L(sub IR) approx. > 10(exp 13)-10(exp 14) Solar L) and have warm colors. They are typically more luminous and warmer than other dusty, z approx.. 2 populations such as submillimeter-selected galaxies and dust-obscured galaxies. These traits are commonly associated with the dust being illuminated by intense active galactic nucleus activity. We hypothesize that the combination of spatially extended Ly-alpha, large amounts of warm IR-luminous dust, and rarity (implying a short-lived phase) can be explained if the galaxies are undergoing brief, intense "feedback" transforming them from an extreme dusty starburst/QSO into a mature galaxy.
We describe the infrared properties of sources detected over approx. 36 deg2 of sky in the GAMA 15-hr equatorial field, using data from both the Herschel Astrophysical Terahertz Large-Area Survey (H-ATLAS) and Wide-field Infrared Survey (WISE). With 5(sigma) point-source depths of 34 and 0.048 mJy at 250 microns and 3.4 microns, respectively, we are able to identify 50.6% of the H-ATLAS sources in the WISE survey, corresponding to a surface density of approx. 630 deg-2. Approximately two-thirds of these sources have measured spectroscopic or optical/near-IR photometric redshifts of z < 1. For sources with spectroscopic redshifts at z < 0.3, we find a linear correlation between the infrared luminosity at 3.4 microns and that at 250 microns, with +/-50% scatter over approx. 1.5 orders of magnitude in luminosity, approx. 10(exp 9) - 10(exp 10.5) Stellar Luminosity. By contrast, the matched sources without previously measured redshifts (r > or approx. 20.5) have 250-350 microns flux density ratios that suggest either high-redshift galaxies (z > or approx. 1.5) or optically faint low-redshift galaxies with unusually low temperatures (T < or approx. 20). Their small 3.4-250 microns flux ratios favor a high-redshift galaxy population, as only the most actively star-forming galaxies at low redshift (e.g., Arp 220) exhibit comparable flux density ratios. Furthermore, we find a relatively large AGN fraction (approx. 30%) in a 12 microns flux-limited subsample of H-ATLAS sources, also consistent with there being a significant population of high-redshift sources in the no-redshift sample.
We present the first results of a study of faint 12 micron sources detected with the WISE survey mission. A deep field around the north Ecliptic pole provides 5sigma sensitivity of around 100microJy, while a side field at high Galactic latitude provides an area of around 10 square degrees. Number counts for these sources are compared to smaller area and higher flux surveys carried out by ISO and IRAS. The WISE survey data show a continued increase in sources out to fainter limits.
The Wide-field Infrared Survey Explorer (WISE), a NASA Medium-Class Explorer (MIDEX) mission, is surveying the entire sky in four bands from 3.4 to 22 microns with a sensitivity hundreds to hundreds of thousands times better than previous all-sky surveys at these wavelengths. The single WISE instrument consists of a 40 cm three-mirror anastigmatic telescope, a two-stage solid hydrogen cryostat, a scan mirror mechanism, and reimaging optics giving 6" resolution (full-width-half-maximum). WISE was placed into a Sun-synchronous polar orbit on a Delta II 7320 launch vehicle on December 14, 2009. NASA selected WISE as a MIDEX in 2002 following a rigorous competitive selection process. To gain further confidence in WISE, NASA extended the development period one year with an option to cancel the mission if certain criteria were not met. MIDEX missions are led by the principal investigator who in this case delegated day-to-day management to the project manager. With a cost cap and relatively short development schedule, it was essential for all WISE partners to work seamlessly together. This was accomplished with an integrated management team representing all key partners and disciplines. The project was developed on budget and on schedule in spite of the need to surmount significant technical challenges. This paper describes our management approach, key challenges and critical decisions made. Results are described from a programmatic, technical and scientific point of view. Lessons learned are offered for projects of this type.
A parallel version of the MOPEX software, which generates mosaics of infrared astronomical images acquired by the Spitzer Space Telescope, extends the capabilities of the prior serial version. In the parallel version, both the input image space and the output mosaic space are divided among the available parallel processors. This is the only software that performs the point-source detection and the rejection of spurious imaging effects of cosmic rays required by Spitzer scientists. This software includes components that implement outlier-detection algorithms that can be fine-tuned for a particular set of image data by use of a number of adjustable parameters. This software has been used to construct a mosaic of the Spitzer Infrared Array Camera Shallow Survey, which comprises more than 17,000 exposures in four wavelength bands from 3.6 to 8 m and spans a solid angle of about 9 square degrees. When this software was executed on 32 nodes of the 1,024-processor Cosmos cluster computer at NASA s Jet Propulsion Laboratory, a speedup of 8.3 was achieved over the serial version of MOPEX. The performance is expected to improve dramatically once a true parallel file system is installed on Cosmos.
We discuss color selection of rare objects in a wide-field multiband survey spanning from the optical to the mid-infrared. Simple color criteria simultaneously identify and distinguish two of the most sought after astrophysical sources: the coolest brown dwarfs and the most distant quasars.We present spectroscopically confirmed examples of each class identified in the IRAC Shallow Survey of the Boo¨tes field of the NOAO Deep Wide-Field Survey. IRAC J142950.8+333011 is a T4.5 brown dwarf at a distance of approximately 30-40 pc, and IRAC J142738.5+331242 is a radio-loud quasar at redshift z=6:12. Our selection criteria identify a total of four candidates over 8 deg2 of the Boo¨tes field. The other two candidates are both confirmed 5:5 < z < 6 quasars, previously reported by Cool et al. (2006).We discuss the implications of these discoveries and conclude that there are excellent prospects for extending such searches to cooler brown dwarfs and higher redshift quasars.
The Wide-field Infrared Survey Explorer (WISE), a NASA MIDEX mission, will survey the entire sky in four bands from 3.3 to 23 microns with a sensitivity 1000 times greater than the IRAS survey. The WISE survey will extend the Two Micron All Sky Survey into the thermal infrared and will provide an important catalog for the James Webb Space Telescope. Using 1024(sup 2) HgCdTe and Si:As arrays at 3.3, 4.7, 12 and 23 microns, WISE will find the most luminous galaxies in the universe, the closest stars to the Sun, and it will detect most of the main belt asteroids larger than 3 km. The single WISE instrument consists of a 40 cm diamond-turned aluminum afocal telescope, a two-stage solid hydrogen cryostat, a scan mirror mechanism, and reimaging optics giving 5 resolution (full-width-half-maximum). The use of dichroics and beamsplitters allows four color images of a 47' x47' field of view to be taken every 8.8 seconds, synchronized with the orbital motion to provide total sky coverage with overlap between revolutions. WISE will be placed into a Sun-synchronous polar orbit on a Delta 7320-10 launch vehicle. The WISE survey approach is simple and efficient. The three-axis-stabilized spacecraft rotates at a constant rate while the scan mirror freezes the telescope line of sight during each exposure. WISE has completed its mission Preliminary Design Review and its NASA Confirmation Review, and the project is awaiting confirmation from NASA to proceed to the Critical Design phase. Much of the payload hardware is now complete, and assembly of the payload will occur over the next year. WISE is scheduled to launch in late 2009; the project web site can be found at www.wise.ssl.berkeley.edu.
The Space Infrared Telescope Facility (SIRTF) is a cornerstone of NASA's Origins program, and will complete NASA's family of Great Observatories when it is launched in December 2001. SIRTF will provide imaging with point source sensitivities ranging from a few microjanskies at 3.6 microns to several millijanskies at 160 microns, land spectroscopy of sources brighter than a millijansky over the 5 to 40 micron range. Over 75% of observing time during SIRTF's expected 5 year lifetime will be available to general investigators from the international community, with the first call for proposals in July 2000. I review SIRTF's capabilities and plans for the study of galaxy formation and evolution. This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration.
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We have observed the rest-frame optical and UV spectra of the luminous, high redshift Infrared Astronomy Satellite (IRAS) source FSC 10214+4724. We find the optical emission lines to be characterized by ratios similar to those found in Seyfert II galaxies. We support the conclusion of previous work that the UV emission lines are similar to those attributed to Active Galactic Nuclei (AGN) rather than to star formation. The ratio H alpha/H beta greater than or equal to 20 (2 sigma lower limit) implies substantial reddening of the narrow line region with A(sub V) greater than 5.5, sufficient to hide a broad line region in our H alpha observations. Given this large inferred reddening and the strength of the UV continuum and emission lines, we conclude (as have others) that simple screen models of reddening are not appropriate for this object. These properties are very similar to those of the infrared luminous galaxies at lower redshift, suggesting that FSC 10244+4724 is the luminous extreme of the same population. We also present H band (1.6 micrometer) imaging polarimetry observations and find that the rest-frame optical emission is unpolarized (P = 3.2% +/- 22.0%). This deep image of the field shows FSC 10214+4724 to possess an unresolved core, with several companions located within 10 sec of the point source. We find it unlikely that this group of objects is physically associated with FSC 10214+4724 at z = 2.3, and we argue that their magnitudes and colors are more consistant with those expected with those expected for galaxies in a foreground group. While galaxy number counts would suggest that such a projection has a low probability of being observed randomly, a foreground group might gravitational lens the z = 2.3 source, making such random statistics inappropriate, and contribute to the large observed luminosity of FSC 10214+4724. Comparison of H band images taken on two occasions one year apart show that FSC 10214+4724 had varied by 0.16 +/- 0.03 mag relative to a nearby star during that time. The UV-optical emission line spectra, the bright dereddened continuum magnitude (K less than 12) of the unresolved core, its extremely large bolometric luminosity, strong UV polarization, and possible variability all suggest that FSC 10214+4724 harbors an obscured AGN. Given that we observe no spectral features attributable to star formation, it appears either that star formation in FSC 10214+4724 is more highly obscured at optical and UV wavelengths than the narrow line region of the AGN, or that the AGN (rather than star formation) dominates the large luminosity of this object.
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In spite of a lookback time of 77 to 89 percent of the age of the universe, Lilly provided evidence that the dominant stellar population in 0902 was surprisingly old, over 1 Gyr. This age estimate was based on the values K = 18.8 and I-K = 4.5 in the central 3.5 x 3.5 inch. At Lilly's suggestion, we reobserved 0902 at K, and in initial reductions of our data found only an upper limit (K greater than 19.5). After extensive experimentation with reduction techniques and correction for low-level systematic effects, we succeeded in extracting a four sigma detection at K = 19.9 in a 4 inch diameter circular aperture. The morphology and location of this detection were more reminescent of the Ly alpha image than of CCD continuum images, and in Mar. 1992, we obtained a narrow band image which included redshifted (OIII) 4959,5007 A line emission at 2.20 microns. This (OIII) image gave a strong detection which demonstrates that most of the central K flux, already reduced by a magnitude, is due to line emission. Our formal line corrected values in a 4 inch aperture are K = 21.5 and R-K = 1.9. Hence, 0902 has been transformed from relaxed maturity into unsettled youth.
The redshift 3.395 radio galaxy B2 0902+34 has been observed at K and in a 0.09 micron wide 2.21 micron filter which includes the redshifted forbidden O III 4959 and 5007 A emission lines. A value of m(K) = 19.9 +/- 0.3 is found in a 4 arcsec aperture, a magnitude fainter than Lilly's (1988) value, while the narrow-band image reveals that most of this flux is actually due to line emission. After correcting for forbidden O III 4959 and 5007A, a color is found which is consistent with the flat F(v) spectrum considered characteristic of a protogalaxy. Ages for the galaxy derived from stellar population models based on the limit R - K less than 3.8 are much younger than those for the I - K = 4.5 value reported by Lilly.
The first spectroscopic detection of H-alpha emission from radio galaxies at z greater than 2 are presented. Strong H-alpha emission is detected at z = 2.429 in B3 0731 + 438, and H-alpha is directed at z = 2.428 in 0406 - 244 at a significant level of greater than 6 sigma. The resulting Ly-alpha/H-alpha ratios for 0731 + 438 and 0406 - 244 are 3.9 and 3.2 with 3 sigma uncertainties of 1.5 for each. A range of possible extinctions is derived depending on the reddening-free Ly-alpha/H-alpha ratio assumed and the extinction curve employed. The most important result of this study is the demonstration that the Ly-alpha/H-alpha ratio in distant galaxies can now be measured with relative ease.