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The Swift Deep Galactic Plane Survey (DGPS) is a Swift Key Project consisting of 380 tiled pointings covering ∼40 deg ^2 of the Galactic plane between longitude 10 < ∣ l ∣ < 30 deg and latitude ∣ b ∣ < 0.5 deg. Each pointing has a 5 ks exposure, yielding a total of 1.9 Ms spread across the entire survey footprint. Phase I observations were carried out between 2017 March and 2021 May. The survey is complete to depth L _X > 10 ^34 erg s ^−1 to the edge of the Galaxy. The main survey goal is to produce a rich sample of new X-ray sources and transients, while also covering a broad discovery space. Here, we introduce the survey strategy and present a catalog of sources detected during Phase I observations. In total, we identify 928 X-ray sources, of which 348 are unique to our X-ray catalog. We report on the characteristics of sources in our catalog and highlight sources newly classified and published by the DGPS team.

We present the results of our X-ray, ultraviolet, and optical follow-up campaigns of 1RXS J165424.6-433758, an X-ray source detected with the Swift Deep Galactic Plane Survey. The source X-ray spectrum (Swift and NuSTAR) is described by thermal bremsstrahlung radiation with a temperature of kT = 10.1 ± 1.2 keV, yielding an X-ray (0.3–10 keV8) luminosity L _X = (6.5 ± 0.8) × 10 ^31 erg s ^−1 at a Gaia distance of 460 pc. Spectroscopy with the Southern African Large Telescope revealed a flat continuum dominated by emission features, demonstrating an inverse Balmer decrement, the λ 4640 Bowen blend, almost a dozen He i lines, and He ii λ 4541, λ 4686, and λ 5411. Our high-speed photometry demonstrates a preponderance of flickering and flaring episodes, and revealed the orbital period of the system, P _orb = 2.87 hr, which fell well within the cataclysmic variable (CV) period gap between 2 and 3 hr. These features classify 1RXS J165424.6-433758 as a nearby polar magnetic CV.

Galactic science encompasses a wide range of subjects in the study of the Milky Way and Magellanic Clouds, from young stellar objects to X-ray binaries. Mapping these populations, and exploring transient phenomena within them, are among the primary science goals of the Vera C. Rubin Observatory’s Legacy Survey of Space and Time. While early versions of the survey strategy dedicated relatively few visits to the Galactic Plane region, more recent strategies under consideration envision a higher cadence within selected regions of high scientific interest. The range of galactic science presents a challenge in evaluating which strategies deliver the highest scientific returns. Here we present metrics designed to evaluate Rubin survey strategy simulations, based on the cadence of observations they deliver within regions of interest to different topics in galactic science, using variability categories defined by timescale. We also compare the fractions of exposures obtained in each filter with those recommended for the different science goals. We find that the baseline _ v2.x simulations deliver observations of the high-priority regions at sufficiently high cadence to reliably detect variability on timescales >10 days or more. Follow-up observations may be necessary to properly characterize variability, especially transients, on shorter timescales. Combining the regions of interest for all the science cases considered, we identify those areas of the Galactic Plane and Magellanic Clouds of highest priority. We recommend that these refined survey footprints be used in future simulations to explore rolling cadence scenarios, and to optimize the sequence of observations in different bandpasses.

During the Zwicky Transient Facility (ZTF) Phase I operations, 78 hydrogen-poor superluminous supernovae (SLSNe-I) were discovered in less than 3 yr, constituting the largest sample from a single survey. This paper (Paper I) presents the data, including the optical/UV light curves and classification spectra, while Paper II in this series will focus on the detailed analysis of the light curves and modeling. Our photometry is primarily taken by ZTF in the g , r , and i bands, and with additional data from other ground-based facilities and Swift. The events of our sample cover a redshift range of z = 0.06 − 0.67, with a median and 1 σ error (16% and 84% percentiles) of ${z}_{\mathrm{med}}={0.265}_{-0.135}^{+0.143}$ . The peak luminosity covers −22.8 mag ≤ M _g _,peak ≤ −19.8 mag, with a median value of $-{21.48}_{-0.61}^{+1.13}$ mag. The light curves evolve slowly with a mean rest-frame rise time of t _rise = 41.9 ± 17.8 days. The luminosity and timescale distributions suggest that low-luminosity SLSNe-I with a peak luminosity ∼−20 mag or extremely fast-rising events (

We present analysis of the light curves (LCs) of 77 hydrogen-poor superluminous supernovae (SLSNe I) discovered during the Zwicky Transient Facility Phase I operation. We find that the majority (67%) of the sample can be fit equally well by both magnetar and ejecta–circumstellar medium (CSM) interaction plus ^56 Ni decay models. This implies that LCs alone cannot unambiguously constrain the physical power sources for an SLSN I. However, 23% of the sample show inverted V-shape, steep-declining LCs or features of long rise and fast post-peak decay, which are better described by the CSM+Ni model. The remaining 10% of the sample favors the magnetar model. Moreover, our analysis shows that the LC undulations are quite common, with a fraction of 18%–44% in our gold sample. Among those strongly undulating events, about 62% of them are found to be CSM-favored, implying that the undulations tend to occur in the CSM-favored events. Undulations show a wide range in energy and duration, with median values (and 1 σ errors) being as $1.7{ \% }_{-0.7 \% }^{+1.5 \% }\,{E}_{\mathrm{rad},\mathrm{total}}$ and ${28.8}_{-9.1}^{+14.4}$ days, respectively. Our analysis of the undulation timescales suggests that intrinsic temporal variations of the central engine can explain half of the undulating events, while CSM interaction (CSI) can account for the majority of the sample. Finally, all of the well-observed He-rich SLSNe Ib either have strongly undulating LCs or the LCs are much better fit by the CSM+Ni model. These observations imply that their progenitor stars have not had enough time to lose all of the He-envelopes before supernova explosions, and H-poor CSM are likely to present in these events.

We have commenced a multiyear program, the Caltech-NRAO Stripe 82 Survey (CNSS), to search for radio transients with the Jansky VLA in the Sloan Digital Sky Survey Stripe 82 region. The CNSS will deliver five epochs over the entire ∼270 deg2 of Stripe 82, an eventual deep combined map with an rms noise of ∼40 μJy and catalogs at a frequency of 3 GHz, and having a spatial resolution of 3″. This first paper presents the results from an initial pilot survey of a 50 deg2 region of Stripe 82, involving four epochs spanning logarithmic timescales between 1 week and 1.5 yr, with the combined map having a median rms noise of 35 μJy. This pilot survey enabled the development of the hardware and software for rapid data processing, as well as transient detection and follow-up, necessary for the full 270 deg2 survey. Data editing, calibration, imaging, source extraction, cataloging, and transient identification were completed in a semi-automated fashion within 6 hr of completion of each epoch of observations, using dedicated computational hardware at the NRAO in Socorro and custom-developed data reduction and transient detection pipelines. Classification of variable and transient sources relied heavily on the wealth of multiwavelength legacy survey data in the Stripe 82 region, supplemented by repeated mapping of the region by the Palomar Transient Factory. A total of % of the few thousand detected point sources were found to vary by greater than 30%, consistent with similar studies at 1.4 and 5 GHz. Multiwavelength photometric data and light curves suggest that the variability is mostly due to shock-induced flaring in the jets of active galactic nuclei (AGNs). Although this was only a pilot survey, we detected two bona fide transients, associated with an RS CVn binary and a dKe star. Comparison with existing legacy survey data (FIRST, VLA-Stripe 82) revealed additional highly variable and transient sources on timescales between 5 and 20 yr, largely associated with renewed AGN activity. The rates of such AGNs possibly imply episodes of enhanced accretion and jet activity occurring once every ∼40,000 yr in these galaxies. We compile the revised radio transient rates and make recommendations for future transient surveys and joint radio-optical experiments. [ABSTRACT FROM AUTHOR]

We present optical and near-infrared (NIR) light curves and optical spectra of SN 2013dx, associated with the nearby (redshift 0.145) gamma-ray burst GRB 130702A. The prompt isotropic gamma-ray energy released from GRB 130702A is measured to be erg (1 keV to 10 MeV in the rest frame), placing it intermediate between low-luminosity GRBs like GRB 980425/SN 1998bw and the broader cosmological population. We compare the observed light curves of SN 2013dx to a SN 1998bw template, finding that SN 2013dx evolves ∼20% faster (steeper rise time), with a comparable peak luminosity. Spectroscopically, SN 2013dx resembles other broad-lined SNe Ic, both associated with (SN 2006aj and SN 1998bw) and lacking (SN 1997ef, SN 2007I, and SN 2010ah) gamma-ray emission, with photospheric velocities around peak of ∼ 21,000 km s−1. We construct a quasi-bolometric () light curve for SN 2013dx, only the fifth GRB-associated SN with extensive NIR coverage and the third with a bolometric light curve extending beyond . Together with the measured photospheric velocity, we derive basic explosion parameters using simple analytic models. We infer a 56Ni mass of , an ejecta mass of , and a kinetic energy of erg (statistical uncertainties only), consistent with previous GRB-associated supernovae. When considering the ensemble population of GRB-associated supernovae, we find no correlation between the mass of synthesized 56Ni and high-energy properties, despite clear predictions from numerical simulations that should correlate with the degree of asymmetry. On the other hand, clearly correlates with the kinetic energy of the supernova ejecta across a wide range of core-collapse events. [ABSTRACT FROM AUTHOR]

We present the results from coordinated X-ray observations of the ultraluminous X-ray source NGC 5204 X-1 performed by the Nuclear Spectroscopic Telescope Array and XMM-Newton in early 2013. These observations provide the first detection of NGC 5204 X-1 above , extending the broadband coverage to . The observations were carried out in two epochs separated by approximately 10 days, and showed little spectral variation with an observed luminosity of erg s−1. The broadband spectrum robustly confirms the presence of a clear spectral downturn above seen in some previous observations. This cutoff is inconsistent with the standard low/hard state seen in Galactic black hole binaries, as would be expected from an intermediate-mass black hole accreting at significantly sub-Eddington rates given the observed luminosity. The continuum is apparently dominated by two optically thick thermal-like components, potentially accompanied by a faint high-energy tail. The broadband spectrum is likely associated with an accretion disk that differs from a standard Shakura & Sunyaev thin disk. [ABSTRACT FROM AUTHOR]

Objective: To identify which subjective and objective tests do content experts utilize to help guide return to sport (RTS) decision making for an athlete after an upper extremity (UE) injury?, Methods: A modified Delphi survey was utilized, including content experts in UE rehabilitation. Survey items were identified based on a literature review identifying current best evidence and practice for UE RTS decision making. Content experts (n = 52) were identified, having a minimum of 10 years of experience with rehabilitation of UE athletic injuries, and 5 years of experience using an UE RTS algorithm to guide decision making., Results: Expert consensus was achieved on a combination of tests utilized within an UE RTS algorithm: 1. Tissue healing time frame is an important consideration in RTS decision making; 2. Patient reported outcome measures should be utilized specifically, DASH and NPRS 3. Strength is measured by handheld dynamometer and is an important consideration. 4. ROM should be utilized and is an important consideration. 5. Physical performance tests utilized include: Closed Kinetic Chain Upper Extremity Stability test, Seated shot-put test and lower extremity/core tests., Conclusions: This survey reached expert consensus on which subjective and objective measures to utilize to evaluate RTS readiness after UE injury., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Detecting gravitationally lensed supernovae is among the biggest challenges in astronomy. It involves a combination of two very rare phenomena: catching the transient signal of a stellar explosion in a distant galaxy and observing it through a nearly perfectly aligned foreground galaxy that deflects light towards the observer. Here we describe how high-cadence optical observations with the Zwicky Transient Facility, with its unparalleled large field of view, led to the detection of a multiply imaged type Ia supernova, SN Zwicky, also known as SN 2022qmx. Magnified nearly 25-fold, the system was found thanks to the standard candle nature of type Ia supernovae. High-spatial-resolution imaging with the Keck telescope resolved four images of the supernova with very small angular separation, corresponding to an Einstein radius of only θ E  = 0.167″ and almost identical arrival times. The small θ E and faintness of the lensing galaxy are very unusual, highlighting the importance of supernovae to fully characterize the properties of galaxy-scale gravitational lenses, including the impact of galaxy substructures., Competing Interests: Competing interestsThe authors declare no competing interests., (© The Author(s) 2023, corrected publication 2023.)

Background/purpose: Return to play decision making for upper extremity injuries is challenging due to a lack of evidence-based protocols and testing. Current guidelines utilize tests and measures with minimal evidence on re-injury risks and prediction. The purpose of this case series is to highlight a functional testing algorithm for upper extremities injuries and the outcomes for the patients that followed it., Study Design: Case series., Case Descriptions: Six subjects (18 - 21 years old) who underwent shoulder capsulolabral repair secondary to recurrent instability and/or unyielding pain are included. All subjects underwent a criterion-based rehabilitation program before being assessed with the authors' upper extremity functional testing algorithm. The upper extremity functional testing algorithm consists of measures of active range of motion (AROM), passive range of motion (PROM), peak isometric force, a fatigue testing battery, and the closed kinetic chain upper extremity stability test (CKCUEST) to assess readiness for return to sport., Outcomes: All athletes achieved > 90% symmetry on at least two out of three tests during a fatigue testing protocol and at least 25 touches on the CKCUEST. All of the athletes returned to unrestricted football the season following surgical intervention. None of the athletes sustained an additional glenohumeral subluxation, dislocation, or upper extremity injury requiring surgical intervention for the remainder of their athletic careers (six years)., Discussion: The presented cases help to illustrate the effectiveness of the upper extremity functional testing algorithm to assess return to sport readiness for male collegiate football athletes. The algorithm included testing of AROM/PROM and strength that is typically used, but also included the CKCUEST and fatigue testing to further challenge and assess the upper extremity prior to returning to sports., Level of Evidence: 4., (© 2020 by the Sports Physical Therapy Section.)

Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and the delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet., (Copyright © 2017, American Association for the Advancement of Science.)