Astro arXiv | astro-ph.IM

Improving Performance in Java: TOPCAT and STILTS by Mark Taylor. on Wednesday 30 November TOPCAT and STILTS are mature Java desktop applications for working with tabular data that have always had a focus on efficiency for large or very large data sets. This paper presents some progress, experience and lessons learned from efforts over recent years to improve performance further by multithreading key algorithms as well as other strategies. arXiv:...

Laue lenses: Focusing optics for hard X soft Gamma-ray Astronomy by L Ferro et al. on Wednesday 30 November Hard X-/soft Gamma-ray astronomy is a key field for the study of important astrophysical phenomena such as the electromagnetic counterparts of gravitational waves, gamma-ray bursts, black holes physics and many more. However, the spatial localization, imaging capabilities and sensitivity of the measurements are strongly limited for the energy range $>$70 keV due to the lack of focusing...

The MUSE second-generation VLT instrument by Bacon R. et al. on Wednesday 30 November The Multi Unit Spectroscopic Explorer (MUSE) is a second-generation VLT panoramic integral-field spectrograph currently in manufacturing, assembly and integration phase. MUSE has a field of 1x1 arcmin2 sampled at 0.2x0.2 arcsec2 and is assisted by the VLT ground layer adaptive optics ESO facility using four laser guide stars. The instrument is a large assembly of 24 identical high performance integral field...

Panel Discussion: Practical Problem Solving for Machine Learning by Guillermo Cabrera et al. on Wednesday 30 November Machine Learning is a powerful tool for astrophysicists, which has already had significant uptake in the community. But there remain some barriers to entry, relating to proper understanding, the difficulty of interpretability, and the lack of cohesive training. In this discussion session we addressed some of these questions, and suggest how the field may move forward. arXiv:...

JWST NIRCam Defocused Imaging: Photometric Stability Performance and How it Can Sense Mirror Tilts by Everett Schlawin et al. on Wednesday 30 November We use JWST NIRCam short wavelength photometry to capture a transit lightcurve of the exoplanet HAT-P-14 b to assess performance as part of instrument commissioning. The short wavelength precision is 152 ppm per 27 second integration as measured over the full time series compared to a theoretical limit of 107 ppm, after corrections to...

Optimal frequency-domain analysis for spacecraft time series: Introducing the missing-data multitaper power spectrum estimator by Sarah E. Dodson-Robinson et al. on Wednesday 30 November While the Lomb-Scargle periodogram is foundational to astronomy, it has a significant shortcoming: its variance does not decrease as more data are acquired. Statisticians have a 60-year history of developing variance-suppressing power spectrum estimators, but most are not used in astronomy because they are...

Visual Magnitude of the BlueWalker 3 Satellite by Anthony Mallama et al. on Wednesday 30 November Observations have been carried out in order to assess the optical characteristics of the BlueWalker 3 spacecraft which is the prototype for a new satellite constellation. The illumination phase function has been determined and evaluated. The average visual magnitude when seen overhead at the beginning or ending of astronomical twilight is found to be +1.4. arXiv:...

ASTENA: a mission concept for a deep study of the transient gamma-ray sky and for nuclear astrophysics by E. Virgilli et al. on Wednesday 30 November Gamma-ray astronomy is a branch whose potential has not yet been fully exploited. The observations of elemental and isotopic abundances in supernova (SN) explosions are key probes not only of the stellar structure and evolution but also for understanding the physics that makes Type-Ia SNe as standard candles for the study of the Universe...

Estimating effective wind speed from Gemini Planet Imager's adaptive optics data using covariance maps by Daniel M. Levinstein et al. on Wednesday 30 November The Earth's turbulent atmosphere results in speckled and blurred images of astronomical objects when observed by ground based visible and near-infrared telescopes. Adaptive optics (AO) systems are employed to reduce these atmospheric effects by using wavefront sensors (WFS) and deformable mirrors. Some AO systems are not fast enough to...

The Spectroscopic Classification of Astronomical Transients SCAT Survey: Overview, Pipeline Description, Initial Results, and Future Plans by M. A. Tucker et al. on Wednesday 30 November We present the Spectroscopic Classification of Astronomical Transients (SCAT) survey, which is dedicated to spectrophotometric observations of transient objects such as supernovae and tidal disruption events. SCAT uses the SuperNova Integral-Field Spectrograph (SNIFS) on the University of Hawai'i 2.2-meter...

The performance of the MAGIC telescopes using deep convolutional neural networks with CTLearn by T. Miener et al. on Wednesday 30 November The Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescope system is located on the Canary Island of La Palma and inspects the very high-energy (VHE, few tens of GeV and above) gamma-ray sky. MAGIC consists of two imaging atmospheric Cherenkov telescopes (IACTs), which capture images of the air showers originating from the absorption of gamma rays...

Satellite Constellation Avoidance with the Rubin Observatory Legacy Survey of Space and Time by Jinghan Alina Hu et al. on Wednesday 30 November We investigate a novel satellite avoidance strategy to mitigate the impact of large commercial satellite constellations in low-Earth orbit on the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST). We simulate the orbits of currently planned Starlink and OneWeb constellations ($\sim$40,000 satellites) to test how effectively an...

Bayesian modelling of scattered light in the LIGO interferometers by Rhiannon Udall et al. on Wednesday 30 November Excess noise from scattered light poses a persistent challenge in the analysis of data from gravitational wave detectors such as LIGO. We integrate a physically motivated model for the behavior of these "glitches" into a standard Bayesian analysis pipeline used in gravitational wave science. This allows for the inference of the free parameters in this model, and subtraction of...

Using a Conditional Generative Adversarial Network to Control the Statistical Characteristics of Generated Images for IACT Data Analysis by Julia Dubenskaya et al. on Wednesday 30 November Generative adversarial networks are a promising tool for image generation in the astronomy domain. Of particular interest are conditional generative adversarial networks (cGANs), which allow you to divide images into several classes according to the value of some property of the image, and then specify the...

Spectroscopic time series performance of the Mid-Infrared Instrument on the JWST by Jeroen Bouwman et al. on Wednesday 30 November We present here the first ever mid-infrared spectroscopic time series observation of the transiting exoplanet \object{L 168-9 b} with the Mid-Infrared Instrument (MIRI) on the James Webb Space Telescope. The data were obtained as part of the MIRI commissioning activities, to characterize the performance of the Low Resolution Spectroscopy (LRS) mode for these...

Adding Workflow Management Flexibility to LSST Pipelines Execution by Michelle Gower et al. on Wednesday 30 November Data processing pipelines need to be executed at scales ranging from small runs up through large production data release runs resulting in millions of data products. As part of the Rubin Observatory's pipeline execution system, BPS is the abstraction layer that provides an interface to different Workflow Management Systems (WMS) such as HTCondor and PanDA. During the...

3UCubed: The IMAP Student Collaboration CubeSat Project by Marcus Alfred et al. on Wednesday 30 November The 3UCubed project is a 3U CubeSat being jointly developed by the University of New Hampshire, Sonoma State University, and Howard University as a part of the NASA Interstellar Mapping and Acceleration Probe, IMAP, student collaboration. This project comprises of a multidisciplinary team of undergraduate students from all three universities. The mission goal of the 3UCubed is to...

GECAM Localization of High Energy Transients and the Systematic Error by Yi Zhao et al. on Wednesday 30 November Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) is a pair of microsatellites (i.e. GECAM-A and GECAM-B) dedicated to monitoring gamma-ray transients including gravitational waves high-energy electromagnetic counterparts, Gamma-ray Bursts, Soft Gamma-ray Repeaters, Solar Flares and Terrestrial Gamma-ray Flashes. Since launch in December 2020,...

FIREBall-2: flight preparation of a proven balloon payload to image the intermediate redshift circumgalactic medium by Vincent Picouet et al. on Wednesday 30 November FIREBall-2 is a stratospheric balloon-borne 1-m telescope coupled to a UV multi-object slit spectrograph designed to map the faint UV emission surrounding z~0.7 galaxies and quasars through their Lyman-alpha line emission. This spectro-imager had its first launch on September 22nd 2018 out of Ft. Sumner, NM, USA. Because the...

A Bayesian approach to RFI mitigation by S. A. K. Leeney et al. on Wednesday 30 November Radio Frequency Interference (RFI) is an endemic problem in radio astronomy. Information in contaminated frequency channels is lost and it can lead to significant systematic error if not properly modelled. In this paper we propose a RFI mitigation methodology that takes a Bayesian approach, where contaminated data is both flagged and managed as part of a single step fitting process. To the authors...