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UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXII 2021San Diego1 August 2021 through 5 August 2021Code 172616.-- Proceedings of SPIE - The International Society for Optical Engineering, Volume 118212021 Article number 1182109, The Gamow Explorer will use Gamma Ray Bursts (GRBs) to: 1) probe the high redshift universe (z < 6) when the first stars were born, galaxies formed and Hydrogen was reionized; and 2) enable multi-messenger astrophysics by rapidly identifying Electro-Magnetic (IR/Optical/X-ray) counterparts to Gravitational Wave (GW) events. GRBs have been detected out to z ∼ 9 and their afterglows are a bright beacon lasting a few days that can be used to observe the spectral fingerprints of the host galaxy and intergalactic medium to map the period of reionization and early metal enrichment. Gamow Explorer is optimized to quickly identify high-z events to trigger follow-up observations with JWST and large ground-based telescopes. A wide field of view Lobster Eye X-ray Telescope (LEXT) will search for GRBs and locate them with arc-minute precision. When a GRB is detected, the rapidly slewing spacecraft will point the 5 photometric channel Photo-z Infra-Red Telescope (PIRT) to identify high redshift (z < 6) long GRBs within 100s and send an alert within 1000s of the GRB trigger. An L2 orbit provides < 95% observing efficiency with pointing optimized for follow up by the James Webb Space Telescope (JWST) and ground observatories. The predicted Gamow Explorer high-z rate is, With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709

We present a survey of the Orion A and B molecular clouds undertaken with the IRAC and MIPS instruments onboard Spitzer. In total, five distinct fields were mapped covering 9 sq. degrees in five mid-IR bands spanning 3-24 microns. The survey includes the Orion Nebula Cluster, the Lynds 1641, 1630 and 1622 dark clouds, and the NGC 2023, 2024, 2068 and 2071 nebulae. These data are merged with the 2MASS point source catalog to generate a catalog of eight band photometry. We identify 3479 dusty young stellar objects (YSOs) in the Orion molecular clouds by searching for point sources with mid-IR colors indicative of reprocessed light from dusty disks or infalling envelopes. The YSOs are subsequently classified on the basis of their mid-IR colors and their spatial distributions are presented. We classify 2991 of the YSOs as pre-main sequence stars with disks and 488 as likely protostars. Most of the sources were observed with IRAC in 2-3 epochs over 6 months; we search for variability between the epochs by looking for correlated variability in the 3.6 and 4.5 micron bands. We find that 50% of the dusty YSOs show variability. The variations are typically small (0.2 mag.) with the protostars showing a higher incidence of variability and larger variations. The observed correlations between the 3.6, 4.5, 5.8 and 8 micron variability suggests that we are observing variations in the heating of the inner disk due to changes in the accretion luminosity or rotating accretion hot spots., Accepted to the Astronomical Journal. A full resolution version of the paper and the point source catalog can be found at http://astro1.physics.utoledo.edu/~megeath/Orion/The_Spitzer_Orion_Survey.html

We present preliminary results on 24micron detections of luminous infrared galaxies at z>1 with the Multiband Imaging Photometer for Spitzer (MIPS). Observations were performed in the Lockman Hole and the Extended Groth Strip (EGS), and were supplemented by data obtained with the Infrared Array Camera (IRAC) between 3 and 9microns. The positional accuracy of ~2arcsec for most MIPS/IRAC detections provides unambiguous identifications of their optical counterparts. Using spectroscopic redshifts from the Deep Extragalactic Evolutionary Probe survey, we identify 24micron sources at z>1 in the EGS, while the combination of the MIPS/IRAC observations with $BVRIJHK$ ancillary data in the Lockman Hole also shows very clear cases of galaxies with photometric redshifts at 1=M*) galaxy counterparts. It is the first time that this population of luminous objects is detected up to z~2.5 in the infrared. Our work demonstrates the ability of the MIPS instrument to probe the dusty Universe at very high redshift, and illustrates how the forthcoming Spitzer deep surveys will offer a unique opportunity to illuminate a dark side of cosmic history not explored by previous infrared experiments., Accepted for publication in the Spitzer Special Issue of ApJS, 4 pages, 2 figures. 1 table

We use the source counts measured with the Multiband Imaging Photometer for Spitzer (MIPS) at 24, 70, and 160 microns to determine the 5-sigma confusion limits due to extragalactic sources: 56 micro-Jy, 3.2 and 40 mJy at 24, 70 and 160 microns, respectively. We also make predictions for confusion limits for a number of proposed far infrared missions of larger aperture (3.5 to 10m diameter)., Comment: Accepted for Publication in ApJS Special Issue on Spitzer. 4 pages, 2 B&W figures. emulateapj. Also available at http://ssc.spitzer.caltech.edu/pubs/journal2004.html

The yeast ADR1 protein contains two zinc finger domains that are essential for its role in transcriptional activation of alcohol dehydrogenase (ADH2). These domains are thought to function as DNA-binding structures. An ADR1-beta-galactosidase fusion protein made in Escherichia coli and containing the finger domains of ADR1 binds in vitro in a zinc-dependent manner to DNA fragments containing the two ADH2 upstream activation sequences. The strongest binding is to upstream activation sequence 1, a 22-base-pair palindrome.

The ISO (Infrared Space Observatory) Short Wavelength Spectrometer (SWS) employs four different types of detectors, which will all be operated at a low flux. Preliminary results of an extensive characterization of these detectors, both in the flight instrument and in a laboratory setup, are presented. In general, the performance of the instrument is as expected and quite low instrument noise equivalent powers are achieved (approximately 10 to the minus 17th power W/square root of Hz). However, the behavior of at least one of the detector types, Si:Sb, is troublesome. Characteristic features of this behavior are presented: long time transient response, memory effects, hook effects and excess noise. The Si:Sb transient responses can be described by two time constants. In contrast with the amplitude of the transient responses, these time constants depend only weakly on illumination power, temperature and bias voltage. This anomalous detector behavior implies specific designs of the observation strategies, which have to avoid 'flat-fielding' difficulties.

Spectra taken with the Short Wavelength Spectrometer on board of the Infrared Space Observatory of dust shells around evolved oxygen-rich stars reveal the presence of several emission features at wavelengths between 20 and 45 mu m. These features have a range of widths and strengths, but are all narrow compared to the well-known amorphous silicate bands at 9.7 and 18 mu m. The emission peaks are tentatively identified with crystalline forms of silicates such as pyroxenes and olivine. The emission features tend to be more prominent for objects with cooler dust shells (T