The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Launching a saliva-based SARS-CoV-2 surveillance testing program on a university campus.

Regular surveillance testing of asymptomatic individuals for SARS-CoV-2 has been center to SARS-CoV-2 outbreak prevention on college and university campuses. Here we describe the voluntary saliva testing program instituted at the University of California, Berkeley during an early period of the SARS-CoV-2 pandemic in 2020. The program was administered as a research study ahead of clinical implementation, enabling us to launch surveillance testing while continuing to optimize the assay. Results of both the testing protocol itself and the study participants' experience show how the program succeeded in providing routine, robust testing capable of contributing to outbreak prevention within a campus community and offer strategies for encouraging participation and a sense of civic responsibility

Launching a saliva-based SARS-CoV-2 surveillance testing program on a university campus.

Regular surveillance testing of asymptomatic individuals for SARS-CoV-2 has been center to SARS-CoV-2 outbreak prevention on college and university campuses. Here we describe the voluntary saliva testing program instituted at the University of California, Berkeley during an early period of the SARS-CoV-2 pandemic in 2020. The program was administered as a research study ahead of clinical implementation, enabling us to launch surveillance testing while continuing to optimize the assay. Results of both the testing protocol itself and the study participants' experience show how the program succeeded in providing routine, robust testing capable of contributing to outbreak prevention within a campus community and offer strategies for encouraging participation and a sense of civic responsibility

Computed Tomography (CT) of five samples of the Sutter's Mill CM2 chondrite.

These files supplement Jenniskens et al. (2012), a comprehensive description of the April 22, 2012 fall and the petrology of the Sutter‟s Mill CM2 chondrite breccia. Here, we present 3-dimensional scans of individual stones of this meteorite. A “Methods” document in this repository records particulars of CT (see Ebel and Rivers 2007). In the Science paper, we note that “samples SM3 and SM9 appear to contain a dominant lithology characterized by abundant 200 to 400 μm diameter clasts (chondrules or CAIs), and 0.05 - 0.15 μm metal oxide or sulfide grains. A second lithology, with higher average atomic mass (Z) matrix and more abundant clasts, appears as irregular, angular lithic fragments many mm in size. At least one metal grain ~250 μm across, was observed, surrounded by a halo ~750 μm wide, of oxidized or sulfidized metal. It is unlikely that such a grain would be sampled by random cutting. Several clasts larger than 1 mm include a low-Z spherical object that appears to be concentrically zoned, and a similar object with zoned high-Z (metal) and low-Z (silicate) layers. While the samples are fractured, and metal grains appear to be altered, no high-Z veins (e.g., FeO-rich) are observed.” And, “the meteorites studied so far exhibit a dominant, primary lithology that is the host for multiple types of exotic lithic clasts.” This lithology is evident in most of SM3. In SM3_13A, at ~30/45 sec running time, more lithic clasts appear, and a large metal-cored grain rimmed by metal sulfide or oxide, appears briefly. The oriented sample SM51 illustrates the asymmetry of fusion crust, thick on the trailing side, very thin on the leading side (top of movie), and thickest at the „lip‟ between these surfaces (image right). A slightly brighter clast (higher average Z) that intersects the leading side fusion crust at ~60/100 sec illustrates a small effect of its composition on crust thickness and composition. A clast-poor lithology is prevalent through the first half of the stack. A large metal grain is present at ~57/100. Two large chondrules appear in SM51 at ~72/100 sec, and the lithology between there and the end is rich in low Z (forsterite-rich?) spherical clasts. In SM54S, fusion crust is very prominent, sweeping left to right in the first few seconds. Several lithologies are present, perhaps four at ~11/83 sec. This sample has some low-Z terrestrial contamination, a reddish clay, that thinly fills small depressions in the sample at the bottom of the images. References Ebel, D. S. and M. L. Rivers. 2007. Meteorite 3-dimensional synchrotron micro-tomography: Methods and applications. Meteoritics and Planetary Science 42: 1627-1646. Jenniskens, P. and 69 coauthors. 2012. Radar enabled recovery of the Sutter‟s Mill meteorite, a carbonaceous chondrite regolith breccia. Science 21 December 2012: Vol. 338 no. 6114 pp. 1583-1587. DOI: 10.1126/science.122716

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4 m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5 m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 yr, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit

Search for intermediate mass black hole binaries in the first observing run of Advanced LIGO

International audienceDuring their first observational run, the two Advanced LIGO detectors attained an unprecedented sensitivity, resulting in the first direct detections of gravitational-wave signals produced by stellar-mass binary black hole systems. This paper reports on an all-sky search for gravitational waves (GWs) from merging intermediate mass black hole binaries (IMBHBs). The combined results from two independent search techniques were used in this study: the first employs a matched-filter algorithm that uses a bank of filters covering the GW signal parameter space, while the second is a generic search for GW transients (bursts). No GWs from IMBHBs were detected; therefore, we constrain the rate of several classes of IMBHB mergers. The most stringent limit is obtained for black holes of individual mass 100  M⊙, with spins aligned with the binary orbital angular momentum. For such systems, the merger rate is constrained to be less than 0.93  Gpc−3 yr−1 in comoving units at the 90% confidence level, an improvement of nearly 2 orders of magnitude over previous upper limits