Publications of the Astronomical Society of the Pacific最新文献

{"title":"The Valuable Long-period Cluster Cepheid KQ Scorpii and other Calibration Candidates","authors":"Daniel Majaess, David G. Turner, Dante Minniti, Javier Alonso-Garcia and Roberto K. Saito","doi":"10.1088/1538-3873/ad7405","DOIUrl":"https://doi.org/10.1088/1538-3873/ad7405","url":null,"abstract":"The classical Cepheid KQ Sco is a valuable anchor for the distance scale because of its long pulsation period (28.ͩ7) and evidence implying membership in the open cluster UBC 1558. Analyses tied to Gaia DR3 astrometry, photometry, spectroscopy, radial velocities, and 2MASS-VVV photometry indicate a common distance of 2.15 ± 0.15 kpc (L21 DR3 corrections applied). Additional cluster Cepheid candidates requiring follow-up are identified, and it is suggested that a team of international researchers could maintain a cluster Cepheid database to guide the broader community to cases where consensus exists.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Parameterization for Finding Solutions for Microlensing Exoplanet Light Curves","authors":"Kylie E. Hall, Jennifer C. Yee, In-Gu Shin, Hongjing Yang and Jiyuan Zhang","doi":"10.1088/1538-3873/ad70d7","DOIUrl":"https://doi.org/10.1088/1538-3873/ad70d7","url":null,"abstract":"The gravitational microlensing method of discovering exoplanets and multi-star systems can produce degenerate solutions, some of which require in-depth analysis to uncover. We propose a new parameter space that can be used to sample potential solutions more efficiently and is more robust at finding all degenerate solutions for the “central-resonant” caustic degeneracy. We identified two new parameters, k and h, that can be sampled in place of the mass ratios and separations of the systems under analysis to identify degenerate solutions. The parameter k is related to the size of the central caustic, Δξc, while h is related to the distance of a point along the k contour from log(s) = 0, where s is the projected planet-host separation. In this work, we present the characteristics of these parameters and the tests we conducted to prove their efficacy.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-amplifier Sensing Charge-coupled Devices for Next Generation Spectroscopy","authors":"Kenneth W. Lin, Armin Karcher, Julien Guy, Stephen E. Holland, William F. Kolbe, Peter E. Nugent, Alex Drlica-Wagner, Ana M. Botti, Javier Tiffenberg","doi":"10.1088/1538-3873/ad716c","DOIUrl":"https://doi.org/10.1088/1538-3873/ad716c","url":null,"abstract":"We present characterization results and performance of a prototype Multiple-Amplifier Sensing (MAS) silicon charge-coupled device (CCD) sensor with 16 channels potentially suitable for faint object astronomical spectroscopy and low-signal, photon-limited imaging. The MAS CCD is designed to reach sub-electron readout noise by repeatedly measuring charge through a line of amplifiers during the serial transfer shifts. Using synchronized readout electronics based on the Dark Energy Spectroscopic Instrument CCD controller, we report a read noise of 1.03 e⁻ rms pix⁻¹ at a speed of 26 <italic toggle=\"yes\">μ</italic>s pix⁻¹ with a single-sample readout scheme where charge in a pixel is measured only once for each output stage. At these operating parameters, we find the amplifier-to-amplifier charge transfer efficiency (ACTE) to be &gt;0.9995 at low counts for all amplifiers but one for which the ACTE is 0.997. This charge transfer efficiency falls above 50,000 electrons for the read-noise optimized voltage configuration we chose for the serial clocks and gates. The amplifier linearity across a broad dynamic range from ∼300 to 35,000 e⁻ was also measured to be ±2.5%. We describe key operating parameters to optimize on these characteristics and describe the specific applications for which the MAS CCD may be a suitable detector candidate.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical Properties of Embedded Clusters in ATLASGAL Clumps with H ii Regions","authors":"J. W. Zhou, Pavel Kroupa, Sami Dib","doi":"10.1088/1538-3873/ad6f44","DOIUrl":"https://doi.org/10.1088/1538-3873/ad6f44","url":null,"abstract":"Using the optimal sampling model, we synthesized the embedded clusters of ATLASGAL clumps with H<sc> ii</sc> regions (H<sc> ii</sc>-clumps). The 0.1 Myr isochrone was used to estimate the bolometric luminosity of each star in an embedded cluster, we also added the accretion luminosity of each star in the embedded cluster. The total bolometric luminosity of synthetic embedded clusters can well fit the observed bolometric luminosity of H<sc> ii</sc>-clumps. More realistically, we considered the age spread in the young star and protostar populations in embedded clusters of H<sc> ii</sc>-clumps by modeling both constant and time-varying star formation histories (SFHs). According to the age distribution of the stellar population, we distributed the appropriate isochrones to each star, and sorted out the fraction of stellar objects that are still protostars (Class 0 and Class I phases) to properly add their accretion luminosities. Compared to a constant SFH, burst-like and time-dependent SFHs can better fit the observational data. We found that as long as 20% of the stars within the embedded cluster are still accreting, the contribution of accretion luminosity will be significant to the total bolometric luminosity of low-mass H<sc> ii</sc>-clumps with mass log₁₀(<italic toggle=\"yes\">M</italic>\u0000_cl/<italic toggle=\"yes\">M</italic>\u0000_⊙) &lt; 2.8. Variations in the accretion rate, the SFE and the initial mass function and more physical processes like the external heating from H<sc> ii</sc> regions and the flaring from pre-main sequence stars and protostars need to be investigated to further explain the excess luminosity of low-mass H<sc> ii</sc>-clumps.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection Limits of Thermal-infrared Observations with Adaptive Optics. I. Observational Data","authors":"J. R. Sauter, W. Brandner, J. Heidt, F. Cantalloube","doi":"10.1088/1538-3873/ad6f45","DOIUrl":"https://doi.org/10.1088/1538-3873/ad6f45","url":null,"abstract":"Ground-based thermal infrared observations face substantial challenges in correcting the predominant background emitted as thermal radiation from the atmosphere and the telescope itself. With the upcoming 40 m class ELTs, unprecedented sensitivities from ground will be reached, underlining the need of even more sophisticated background correction strategies. This study aims to investigate the impact of thermal backgrounds on ground-based observations and identify possible limiting factors in dedicated correction strategies. We evaluate temporal and spatial characteristics of the thermal background in direct imaging data obtained with different telescopes and observation modes. In particular, three distinct data sets, acquired using VLT/NACO and KECK/NIRC2, are analyzed. Our analysis reveals that the observations are not fully photon shot noise limited, but exhibit additional sensitivity losses caused by imperfect background compensation in the different data sets. We identify correlations between background fluctuations and the activity of the adaptive optics system. We hypothesize that the pupil modulation of the adaptive optics mirrors introduces high frequency spatial and temporal fluctuations to the background, which could ultimately constrain the detection limit if they are not compensated adequately.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ejecta Masses in Type Ia Supernovae—Implications for the Progenitor and the Explosion Scenario* * Based in part on observations obtained with the Hobby-Eberly Telescope (HET), which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Ludwig-Maximillians-Universitaet Muenchen, and Georg-August Universitaet Goettingen. The HET is named in honor of its principal benefactors, William P. Hobby and Robert E. Eberly.","authors":"Zsófia Bora, Réka Könyves-Tóth, József Vinkó, Dominik Bánhidi, Imre Barna Bíró, K. Azalee Bostroem, Attila Bódi, Jamison Burke, István Csányi, Borbála Cseh, Joseph Farah, Alexei V. Filippenko, Tibor Hegedüs, Daichi Hiramatsu, Ágoston Horti-Dávid, D. Andrew Howell, Saurabh W. Jha, Csilla Kalup, Máté Krezinger, Levente Kriskovics, Curtis McCully, Megan Newsome, András Ordasi, Estefania Padilla Gonzalez, András Pál, Craig Pellegrino, Bálint Seli, Ádám Sódor, Zsófia Marianna Szabó, Olivér Norton Szabó, Róbert Szakáts, Tamás Szalai, Péter Székely, Giacomo Terreran, Vázsony Varga, Krisztián Vida, Xiaofeng Wang, J. Craig Wheeler","doi":"10.1088/1538-3873/ad6e18","DOIUrl":"https://doi.org/10.1088/1538-3873/ad6e18","url":null,"abstract":"The progenitor system(s) as well as the explosion mechanism(s) of thermonuclear (Type Ia) supernovae are long-standing issues in astrophysics. Here we present ejecta masses and other physical parameters for 28 recent Type Ia supernovae inferred from multiband photometric and optical spectroscopic data. Our results confirm that the majority of SNe Ia show <italic toggle=\"yes\">observable</italic> ejecta masses below the Chandrasekhar-limit (having a mean <italic toggle=\"yes\">M</italic>\u0000_ej ≈ 1.1 ± 0.3 <italic toggle=\"yes\">M</italic>\u0000_⊙), consistent with the predictions of recent sub-<italic toggle=\"yes\">M</italic>\u0000_Ch explosion models. They are compatible with models assuming either single- or double-degenerate progenitor configurations. We also recover a sub-sample of supernovae within 1.2 <italic toggle=\"yes\">M</italic>\u0000_⊙ &lt; <italic toggle=\"yes\">M</italic>\u0000_ej &lt; 1.5 <italic toggle=\"yes\">M</italic>\u0000_⊙ that are consistent with near-Chandrasekhar explosions. Taking into account the uncertainties of the inferred ejecta masses, about half of our SNe are compatible with both explosion models. We compare our results with those in previous studies, and discuss the caveats and concerns regarding the applied methodology.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aggregate Cloud Particle Effects in Exoplanet Atmospheres","authors":"Sanaz Vahidinia, Sarah E. Moran, Mark S. Marley, Jeffrey N. Cuzzi","doi":"10.1088/1538-3873/ad6cf2","DOIUrl":"https://doi.org/10.1088/1538-3873/ad6cf2","url":null,"abstract":"Aerosol opacity has emerged as a critical factor controlling transmission and emission spectra. We provide a simple guideline for the effects of aerosol morphology on opacity and residence time in the atmosphere, as it pertains to transit observations, particularly those with flat spectra due to high altitude aerosols. This framework can be used for understanding complex cloud and haze particle properties before getting into detailed microphysical modeling. We consider high altitude aerosols to be composed of large fluffy particles that can have large residence times in the atmosphere and influence the deposition of stellar flux and/or the emergence of thermal emission in a different way than compact droplet particles, as generally modeled to date for extrasolar planetary atmospheres. We demonstrate the important influence of aggregate particle porosity and composition on the extent of the wavelength independent regime. We also consider how such fluffy particles reach such high altitudes and conclude that the most likely scenario is their local production at high altitudes via UV bombardment and subsequent blanketing of the atmosphere, rather than some mechanism of lofting or transport from the lower atmosphere.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fisheye Night Sky Imager: A Calibrated Tool to Measure Night Sky Brightness","authors":"Li-Wei Hung, Jeremy White, Damon Joyce, Sharolyn J Anderson, Benjamin Banet","doi":"10.1088/1538-3873/ad6bc1","DOIUrl":"https://doi.org/10.1088/1538-3873/ad6bc1","url":null,"abstract":"The Night Skies Team of the U.S. National Park Service (NPS) has developed a new camera system equipped with a fisheye lens to measure night sky brightness. This NPS Fisheye Night Sky Imager comprises a back-illuminated Sony IMX455 CMOS sensor housed in the ZWO ASI6200MM camera, a Johnson V filter, and a Sigma 8 mm F3.5 fisheye lens. All of the components are commercially available. The fisheye lens allows us to capture the entire sky in a single frame. The wide-angle view also introduces calibration challenges. To address this, we have customized tools and devised innovative methods for calibrating the system, including flat-field correction, pixel scale determination, and field of view characterization. Additionally, we use standard stars for precise positional and photometric calibration. Furthermore, we create an open-source Python pipeline to process these fisheye images and leverage Git and GitHub for source code version control and distribution. The resulting images provide a positionally and brightness-calibrated fisheye view of the night sky, with a photometric calibration uncertainty of 0.12 mag. When comparing our Fisheye Night Sky Imager measurements to images taken with other calibrated systems, we reliably achieve consistent results under both dark and bright skies. Our Fisheye Night Sky Imager not only enables rapid assessment of sky quality but also supports the feasibility of establishing permanent monitoring locations. Recognizing that the natural dark sky is a critical element for natural, cultural, educational, and visitor experiences, this new camera system enhances our ability to assess resource conditions and fulfill the NPS mission of conserving resources unimpaired for the enjoyment of this and future generations.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scale-invariant Features of X-Ray Bursts from SGR J1935+2154 Detected by Insight-HXMT","authors":"Xiu-Juan Li, Jia-Mu Liu, Ming Cheng, Yan-Na Wang, Wen-Long Zhang","doi":"10.1088/1538-3873/ad6a8a","DOIUrl":"https://doi.org/10.1088/1538-3873/ad6a8a","url":null,"abstract":"In this work, we restudy the scale-invariant features of X-ray bursts from the soft gamma repeater (SGR) J1935+2154. To compare with previous studies, we choose 75 bursts from a dedicated 33 days-long observation carried out by Insight-HXMT. We investigate the size difference distributions of net counts, duration, and waiting time. It is found that the cumulative difference distributions of net counts and duration follow the <italic toggle=\"yes\">q</italic>-Gaussian models with approximately steady <italic toggle=\"yes\">q</italic>-values, confirming that the scale-invariant features exist in X-ray bursts of SGR J1935+2154. Regarding the varying results of waiting time reported by Sang &amp; Lin and Wei et al, we find that the distributions of waiting time can be well described by the <italic toggle=\"yes\">q</italic>-Gaussian model. Furthermore, the <italic toggle=\"yes\">q</italic>-values of waiting time remain relatively stable at the 3<italic toggle=\"yes\">σ</italic> confidence level, corroborating the scale invariance in the X-ray bursts. Additionally, we note that there is no significant <italic toggle=\"yes\">q</italic>-value evolution across three Insight-HXMT telescopes. These findings statistically affirm that the X-ray bursts from SGR J1935+2154 can be attributed to an fractal-diffusive self-organized criticality system with a plausible Euclidean spatial dimension <italic toggle=\"yes\">S</italic> = 3, implying that X-ray bursts from SGR J1935+2154 and associated astrophysical phenomena may share a similar magnetically dominated stochastic process.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase-resolving the Absorption Signatures of Water and Carbon Monoxide in the Atmosphere of the Ultra-hot Jupiter WASP-121b with GEMINI-S/IGRINS","authors":"Joost P. Wardenier, Vivien Parmentier, Michael R. Line, Megan Weiner Mansfield, Xianyu Tan, Shang-Min Tsai, Jacob L. Bean, Jayne L. Birkby, Matteo Brogi, Jean-Michel Désert, Siddharth Gandhi, Elspeth K. H. Lee, Colette I. Levens, Lorenzo Pino, Peter C. B. Smith","doi":"10.1088/1538-3873/ad5c9f","DOIUrl":"https://doi.org/10.1088/1538-3873/ad5c9f","url":null,"abstract":"Ultra-hot Jupiters (UHJs) are among the best targets for atmospheric characterization at high spectral resolution. Resolving their transmission spectra as a function of orbital phase offers a unique window into the 3D nature of these objects. In this work, we present three transits of the UHJ WASP-121b observed with Gemini-S/IGRINS. For the first time, we measure the phase-dependent absorption signals of CO and H₂O in the atmosphere of an exoplanet, and we find that they are different. While the blueshift of CO increases during the transit, the absorption lines of H₂O become less blueshifted with phase, and even show a redshift in the second half of the transit. These measurements reveal the distinct spatial distributions of both molecules across the atmospheres of UHJs. Also, we find that the H₂O signal is absent in the first quarter of the transit, potentially hinting at cloud formation on the evening terminator of WASP-121b. To further interpret the absorption trails of CO and H₂O, as well as the Doppler shifts of Fe previously measured with VLT/ESPRESSO, we compare the data to simulated transits of WASP-121b. To this end, we post-process the outputs of the global circulation models with a 3D Monte-Carlo radiative transfer code. Our analysis shows that the atmosphere of WASP-121b is subject to atmospheric drag, as previously suggested by small hotspot offsets inferred from phase-curve observations. Our study highlights the importance of phase-resolved spectroscopy in unravelling the complex atmospheric structure of UHJs and sets the stage for further investigations into their chemistry and dynamics.","PeriodicalId":20820,"journal":{"name":"Publications of the Astronomical Society of the Pacific","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}