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Creators/Authors contains: "Street, Rachel"

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  1. A TOM Toolkit plugin module designed to enable users to submit requests for Target-Of-Opportunity observations to the Neil Gehrel's Swift Space Telescope. 
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  2. A TOM Toolkit plugin module to enable users to send and receive messages via the Hermes astronomical messaging service.  Developed in collaboration with the Scaleable Infrastructure for Multi-Messenger Astrophysics project. 
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  3. Framework for building Target and Observation Manager systems for the management of astronomical projects.     v2.19.6 includes a substantial revision to the target model that enables users to customize the parameters and functions associated with the astronomical targets they study, as well as improved target cross-matching. 
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  4. A TOM Toolkit plugin application designed for astrophysical events that are non-localized in position on sky, such as gravitational wave detections.  This plugin includes functionality for gathering and displaying alert information from GraceDB, and can associate a number of targets with each event instance.  It supports the creation of active and retired lists of candidate targets to facilitate follow-up observations. 
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  5. Abstract We describe the results of a new reverberation mapping program focused on the nearby Seyfert galaxy NGC 3227. Photometric and spectroscopic monitoring was carried out from 2022 December to 2023 June with the Las Cumbres Observatory network of telescopes. We detected time delays in several optical broad emission lines, with Hβhaving the longest delay at τ cent = 4.0 0.9 + 0.9 days and Heiihaving the shortest delay with τ cent = 0.9 0.8 + 1.1 days. We also detect velocity-resolved behavior of the Hβemission line, with different line-of-sight velocities corresponding to different observed time delays. Combining the integrated Hβtime delay with the width of the variable component of the emission line and a standard scale factor suggests a black hole mass of M BH = 1.1 0.3 + 0.2 × 10 7 M. Modeling of the full velocity-resolved response of the Hβemission line with the phenomenological codeCARAMELfinds a similar mass of M BH = 1.2 0.7 + 1.5 × 10 7 Mand suggests that the Hβ-emitting broad-line region (BLR) may be represented by a biconical or flared disk structure that we are viewing at an inclination angle ofθi≈ 33° and with gas motions that are dominated by rotation. The new photoionization-based BLR modeling toolBELMACfinds general agreement with the observations when assuming the best-fitCARAMELresults; however,BELMACprefers a thick-disk geometry and kinematics that are equally composed of rotation and inflow. Both codes infer a radially extended and flattened BLR that is not outflowing. 
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  6. Abstract We present the results of a new reverberation mapping campaign for the broad-line active galactic nucleus (AGN) in the edge-on spiral IC 4329A. Monitoring of the optical continuum withV-band photometry and broad emission-line flux variability with moderate-resolution spectroscopy allowed emission-line light curves to be measured for Hβ, Hγ, and Heiiλ4686. We find a time delay of 16.3 2.3 + 2.6 days for Hβ, a similar time delay of 16.0 2.6 + 4.8 days for Hγ, and an unresolved time delay of 0.6 3.9 + 3.9 days for Heii. The time delay for Hβis consistent with the predicted value from the relationship between AGN luminosity and broad-line region radius, after correction for the ∼2.4 mag of intrinsic extinction at 5100 Å. Combining the measured time delay for Hβwith the broad emission-line width and an adopted value of 〈f〉 = 4.8, we find a central supermassive black hole mass of M BH = 6.8 1.1 + 1.2 × 10 7 M. Velocity-resolved time delays were measured across the broad Hβemission-line profile and may be consistent with an “M”-like shape. Modeling of the full reverberation response of Hβwas able to provide only modest constraints on some parameters, but does exhibit agreement with the black hole mass and average time delay. The models also suggest that the AGN structure is misaligned by a large amount from the edge-on galaxy disk. This is consistent with expectations from the unified model of AGNs, in which broad emission lines are expected to be visible only for AGNs that are viewed at relatively face-on inclinations. 
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  7. Abstract We report discovering an exoplanet from following up a microlensing event alerted by Gaia. The event Gaia22dkv is toward a disk source rather than the traditional bulge microlensing fields. Our primary analysis yields a Jovian planet with M p = 0.59 0.05 + 0.15 M J at a projected orbital separation r = 1.4 0.3 + 0.8 au, and the host is a ∼1.1Mturnoff star at ∼1.3 kpc. At r 14 , the host is far brighter than any previously discovered microlensing planet host, opening up the opportunity to test the microlensing model with radial velocity (RV) observations. RV data can be used to measure the planet’s orbital period and eccentricity, and they also enable searching for inner planets of the microlensing cold Jupiter, as expected from the “inner–outer correlation” inferred from Kepler and RV discoveries. Furthermore, we show that Gaia astrometric microlensing will not only allow precise measurements of its angular Einstein radiusθEbut also directly measure the microlens parallax vector and unambiguously break a geometric light-curve degeneracy, leading to the definitive characterization of the lens system. 
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  8. null (Ed.)
  9. Aims.We investigated the nature of the anomalies appearing in four microlensing events KMT-2020-BLG-0757, KMT-2022-BLG-0732, KMT-2022-BLG-1787, and KMT-2022-BLG-1852. The light curves of these events commonly exhibit initial bumps followed by subsequent troughs that extend across a substantial portion of the light curves. Methods.We performed thorough modeling of the anomalies to elucidate their characteristics. Despite their prolonged durations, which differ from the usual brief anomalies observed in typical planetary events, our analysis revealed that each anomaly in these events originated from a planetary companion located within the Einstein ring of the primary star. It was found that the initial bump arouse when the source star crossed one of the planetary caustics, while the subsequent trough feature occurred as the source traversed the region of minor image perturbations lying between the pair of planetary caustics. Results.The estimated masses of the host and planet, their mass ratios, and the distance to the discovered planetary systems are (Mhost/M,Mplanet/MJ,q/10−3,DL/kpc) = (0.58−0.30+0.33, 10.71−5.61+6.17, 17.61 ± 2.25, 6.67−1.30+0.93) for KMT-2020-BLG-0757, (0.53−0.31+0.31, 1.12−0.65+0.65, 2.01 ± 0.07, 6.66−1.84+1.19) for KMT-2022-BLG-0732, (0.42−0.23+0.32, 6.64−3.64+4.98, 15.07 ± 0.86, 7.55−1.30+0.89) for KMT-2022-BLG-1787, and (0.32−0.19+0.34, 4.98−2.94+5.42, 8.74 ± 0.49, 6.27−1.15+0.90) for KMT-2022-BLG-1852. These parameters indicate that all the planets are giants with masses exceeding the mass of Jupiter in our solar system and the hosts are low-mass stars with masses substantially less massive than the Sun. 
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