Research notes of the AAS最新文献

{"title":"The Dispersion Relation of Massive Photons in Plasma: A Comment on “Bounding the Photon Mass with Ultrawide Bandwidth Pulsar Timing Data and Dedispersed Pulses of Fast Radio Bursts”","authors":"Bao Wang, Jun-Jie Wei","doi":"10.3847/2515-5172/ad7676","DOIUrl":"https://doi.org/10.3847/2515-5172/ad7676","url":null,"abstract":"The dispersion measures of fast radio bursts have been identified as a powerful tool for testing the zero-mass hypothesis of the photon. The classical approach treats the massive photon-induced and plasma-induced time delays as two separate phenomena. Recently, Y.-B. Wang et al. suggested that the joint influence of the nonzero photon mass and plasma effects should be considered, and proposed a revised time delay for massive photons propagating in a plasma medium, denoted as <inline-formula>\u0000<tex-math>\u0000<?CDATA ${rm{Delta }}{t}_{{m}_{gamma }}^{{prime} }propto {nu }^{-4}$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:mi mathvariant=\"normal\">Δ</mml:mi><mml:msubsup><mml:mrow><mml:mi>t</mml:mi></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi>m</mml:mi></mml:mrow><mml:mrow><mml:mi>γ</mml:mi></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:mo accent=\"false\">′</mml:mo></mml:mrow></mml:msubsup><mml:mo>∝</mml:mo><mml:msup><mml:mrow><mml:mi>ν</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo><mml:mn>4</mml:mn></mml:mrow></mml:msup></mml:math>\u0000<inline-graphic xlink:href=\"rnaasad7676ieqn1.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula>, which departures from the classical dispersion relation (∝<italic toggle=\"yes\">ν</italic>\u0000⁻²). Here we discuss the derivation presented by Y.-B. Wang et al. and show that the classical dispersion relation remains valid based on Proca equations.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Well-balanced Hydrodynamics for the Piecewise Parabolic Method with Characteristic Tracing","authors":"Michael Zingale","doi":"10.3847/2515-5172/ad76b0","DOIUrl":"https://doi.org/10.3847/2515-5172/ad76b0","url":null,"abstract":"Well-balanced reconstruction techniques have been developed for stellar hydrodynamics to address the challenges of maintaining hydrostatic equilibrium during evolution. I show how to adapt a simple well-balanced method to the piecewise parabolic method for hydrodynamics. A python implementation of the method is provided.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"69 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142217999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dust Grain Properties in Extragalactic Environment Through Supernovae Dust Polarization Observations","authors":"Saikhom Pravash Singh, Archana Soam","doi":"10.3847/2515-5172/ad7675","DOIUrl":"https://doi.org/10.3847/2515-5172/ad7675","url":null,"abstract":"Dust polarization observations of starlight at multi-wavelengths helps us to find maximum polarization, <italic toggle=\"yes\">P</italic>\u0000_max and the corresponding wavelength, <inline-formula>\u0000<tex-math>\u0000<?CDATA ${lambda }_{max }$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msub><mml:mrow><mml:mi>λ</mml:mi></mml:mrow><mml:mrow><mml:mi>max</mml:mi></mml:mrow></mml:msub></mml:math>\u0000<inline-graphic xlink:href=\"rnaasad7675ieqn1.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula>. This <inline-formula>\u0000<tex-math>\u0000<?CDATA ${lambda }_{max }$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msub><mml:mrow><mml:mi>λ</mml:mi></mml:mrow><mml:mrow><mml:mi>max</mml:mi></mml:mrow></mml:msub></mml:math>\u0000<inline-graphic xlink:href=\"rnaasad7675ieqn2.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula> is approximately proportional to average grain size, thereby helping to reveal grain sizes in the intervening medium. We study the average grain sizes in different host galaxies of 4 Type Ia and 10 Type II supernovae through spectropolarimetric observations at multi-wavelengths and compare with the average grain sizes in the diffused interstellar medium of our galaxy. We use archival <italic toggle=\"yes\">P</italic>\u0000_max, <inline-formula>\u0000<tex-math>\u0000<?CDATA ${lambda }_{max }$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msub><mml:mrow><mml:mi>λ</mml:mi></mml:mrow><mml:mrow><mml:mi>max</mml:mi></mml:mrow></mml:msub></mml:math>\u0000<inline-graphic xlink:href=\"rnaasad7675ieqn3.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula> and width of peak of polarization curve (<italic toggle=\"yes\">K</italic>) values from the literature. We plot <italic toggle=\"yes\">P</italic>\u0000_max versus <inline-formula>\u0000<tex-math>\u0000<?CDATA ${lambda }_{max }$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msub><mml:mrow><mml:mi>λ</mml:mi></mml:mrow><mml:mrow><mml:mi>max</mml:mi></mml:mrow></mml:msub></mml:math>\u0000<inline-graphic xlink:href=\"rnaasad7675ieqn4.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula> in color scale that represents <italic toggle=\"yes\">K</italic> and find that grain sizes of some of the galaxies are smaller, some nearly comparable and some larger than typical grain size (≈5500 Å) of our galaxy. This gives us an insight into the different grain properties especially their sizes in external galaxies compared to our galaxy.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ellipse-fitting in Mock Images of TNG50 Barred Galaxies","authors":"Gustavo F. Gonçalves, Rubens E. G. Machado","doi":"10.3847/2515-5172/ad758f","DOIUrl":"https://doi.org/10.3847/2515-5172/ad758f","url":null,"abstract":"Recent studies have utilized the TNG50 simulation to explore barred galaxy morphology. The ellipse-fitting method is commonly used to assess properties of the isophotes in the central region of the disk. This work adapts the ellipse-fitting method to simulated images from TNG50, dealing with the issue of excessively pronounced ellipticities in central regions, whether in mass distribution maps or simulated radiative transfer images. To solve this problem, we introduce synthetic realism in the form of convolution with point spread functions, correcting the misbehavior in central ellipticities. These improvements simplify the application of ellipse-fitting to barred galaxies in the TNG50 simulation, enabling more accurate analysis of properties such as bar length and ellipticity, which would otherwise be more difficult to measure accurately. Thus, we conclude that when measuring shapes of simulated barred galaxies, one should apply realistic smoothing, otherwise the inner ellipticities will not be comparable to observations.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exoplanet Harmony: Confirming Kepler’s Third Law with Kepler and TESS Discoveries","authors":"Jonathan H. Jiang, Jadon Lam","doi":"10.3847/2515-5172/ad74d9","DOIUrl":"https://doi.org/10.3847/2515-5172/ad74d9","url":null,"abstract":"We investigate whether the orbital periods of exoplanets discovered by the Kepler and TESS missions adhere to Kepler’s Third Law, akin to the planets in our solar system. Using data obtained from the NASA Exoplanet Archive (DOI:<ext-link ext-link-type=\"uri\" xlink:href=\"https://doi.org/10.26133/NEA12\" xlink:type=\"simple\">10.26133/NEA12</ext-link>) on 2024 June 24, we analyzed 2659 Kepler observations and 415 TESS observations. Our results demonstrate that the exoplanets observed by both Kepler and TESS missions follow Kepler’s law, with deviations that are within the expected range of observational uncertainties. This confirms that Kepler’s Third Law holds true for exoplanets beyond our solar system.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"mardigras: A Visualization Tool of Theoretical Mass–Radius Relations in the Context of Planetary Science","authors":"Artyom Aguichine","doi":"10.3847/2515-5172/ad7506","DOIUrl":"https://doi.org/10.3847/2515-5172/ad7506","url":null,"abstract":"Over the past two decades, mass–radius relations have become a crucial tool for inferring the bulk composition of exoplanets using only their measured masses and radii. These relations, often referred to as isocomposition curves, are derived from interior structure models by calculating the theoretical radius as a function of mass for a given fixed planetary composition. Each mass–radius curve can be influenced by a variety of parameters, such as planetary composition, age, and equilibrium temperature. Navigating this parameter space can be cumbersome, particularly when models or their results are not open-source. To address this challenge, I have developed MAss–Radius DIaGRAm with Sliders, a visualization tool that enables simple, fast, and interactive exploration of the parameter space that governs mass–radius relations for any given model.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142217842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LIGO-Virgo-KAGRA Limit on Relativistic Interstellar Objects near Earth","authors":"Abraham Loeb","doi":"10.3847/2515-5172/ad73da","DOIUrl":"https://doi.org/10.3847/2515-5172/ad73da","url":null,"abstract":"Relativistic interstellar objects (RISOs) are not constrained by astronomical sky surveys because they are smeared in sky images and at best appear in one frame. Here, I show that irrespective of their nature, RISOs more massive than ∼10¹⁴ g would have been detected by the LIGO-Virgo-KAGRA collaboration through their tidal gravitational signal at a frequency of <italic toggle=\"yes\">f</italic> ∼ 50 Hz within a distance comparable to the Earth radius. This constrains the passage of relativistic primordial black holes or other exotic objects at the local mass density of dark matter near Earth over the past decade.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New Transient Co-orbital Asteroids of Venus","authors":"Valerio Carruba, Maria Helena Moreira Morais, Daniela C. Mourão, Rosana A. N. Araujo, Safwan Aljbaae, Gabriel Caritá, Rita C. Domingos","doi":"10.3847/2515-5172/ad7261","DOIUrl":"https://doi.org/10.3847/2515-5172/ad7261","url":null,"abstract":"Venus has no known natural satellites but has 5 known co-orbitals. These are objects trapped in a 1:1 mean-motion resonance with Venus. Co-orbital configurations include retrograde satellite orbits (RS), tadpole orbits (T) around the Lagrangian equilibrium points L4 or L5, and horseshoe orbits around both L4 and L5 (H). At high eccentricity or inclination, co-orbital configurations may also involve compounds of T and RS (T-RS, T-RS-T), H and RS (H-RS) orbits, or transitions between different co-orbital modes. Here we identify asteroids in 2 RS, 1 L4-tadpole, 2 H-RS, and 2 T-RS orbits, as well as 8 additional asteroids in possible temporary co-orbital status. Although the majority of these objects do not yet have well-characterized orbits, 2020 CL1, and 2020 SB do and are very likely to be new co-orbital asteroids. With the new candidates, Venus would have a population of 20 co-orbital asteroids, comparable to those of Mars and Earth.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A False Positive Transit Candidate for EPIC 211101996 from K2 and TESS Data Identified as Background Eclipsing Binary Gaia DR3 66767847894609792","authors":"René Heller, Milena Hüschen, Jan-Vincent Harre, Stefan Dreizler","doi":"10.3847/2515-5172/ad73bb","DOIUrl":"https://doi.org/10.3847/2515-5172/ad73bb","url":null,"abstract":"Transiting planets around young stars are hard to find due to the enhanced stellar activity. Only a few transiting planets have been detected around stars younger than 100 Myr. We initially detected a transit-like signal in the K2 light curve of a very cool M dwarf star (EPIC 211101996) in the Pleiades open cluster, with an estimated age of about 100 Myr. Our detailed analysis of the per-pixel light curves, detrending with the Wōtan software and transit search with the Transit Least Squares algorithm showed that the source of the signal is a contaminant source (Gaia DR3 66767847894609792) 20″ west of the target. The V-like shape of its phase-folded light curve and eclipse depth of ∼15% suggest that it is a grazing eclipsing binary. The contaminant has hitherto been listed as a single star, which we now identify as an eclipsing stellar binary with a period of about 6 days.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gas Dynamics in the Herbig Ae Star HD 163296 in 2024","authors":"Michael L. Sitko, Ray W. Russell, Monica Pikhartova, William Danchi","doi":"10.3847/2515-5172/ad7381","DOIUrl":"https://doi.org/10.3847/2515-5172/ad7381","url":null,"abstract":"We observed the Herbig Ae star HD 163296 over 9 nights in 2024. On 4 of the nights, the He <sc>i</sc> line at 1.083 <italic toggle=\"yes\">μ</italic>m exhibited a profile rarely seen in the star. Rather than the typical P Cygni profile indicating a net gas outflow, the profile consisted of a deep absorption line with weak emission peaks on either side. These seem to be consistent with either an outflowing bipolar jet, a circular ring of gas orbiting close to the star, and/or accretion columns connecting the inner disk to the star. Given the history of the ejection of Herbi-Haro object in the star’s bipolar jets, these observations should coincide with the very beginning of the ejection event. Coordinated observations with multiple observing techniques over the next decade are warranted.","PeriodicalId":74684,"journal":{"name":"Research notes of the AAS","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}