Accurate visualization of double star astrometric data is essential for effective analysis and interpretation. This article presents a Python toolkit designed for astronomers who need to plot measurements from diverse sources -- historical, Gaia DR3, and the Las Cumbres Observatory (LCO) network -- while maintaining a 1:1 aspect ratio to avoid visually distorting the data. The toolkit is composed of three scripts: one that handles polar coordinates (P.A., separation), one for Cartesian (X, Y) coordinates, and another with the option to include predicted theoretical points. This paper describes the purpose, functionality, and usage of these scripts, including example figures, installation guides, and licensing information. This toolkit has been used by the author and collaborators in published and submitted research on double star systems, demonstrating its versatility for both professional and student-driven investigations.
Modules for Experiments in Stellar Astrophysics (MESA; (Paxton2011, 2013, 2015, 2018, 2019, Jermyn 2023) is a widely used open-source software for modelling stellar evolution. In many studies, the computational grids covers thousands of models (e.g., Joyce et al 2024), which requires a tremendous amount of time and computational effort to process. To streamline data analysis, the mesalab package was developed. This Python-based pipeline is designed to simplify the post-processing of MESA outputs by automatically identifying various stellar evolutionary phases, with a specific focus on the ``blue loop'' -- a blue-ward excursion in the Hertzsprung-Russell Diagram (HRD) for intermediate-mass stars often associated with peculiar pulsational phenomena like ``strange modes.''
We live in an exoplanet revolution, with more than 5,000 exoplanets detected to date. Our ability to characterise individual exoplanets is constantly improving, with exquisite mass and radius measurements for an ever-growing sample of planets, complimented by atmospheric characterisation of lower and lower mass planets. This chapter outlines a complimentary set of observations that uniquely provide bulk elemental compositions for exoplanetary material. Absorption features from metals, including Mg, Fe, Si, O, Ca, Al, Ni and Ti in the white dwarf photosphere characterise the composition of accreted planetary material. These observations highlight the diversity in composition across exoplanetary systems including volatile content and probe key geological processes including the formation of iron cores. Thanks to the many white dwarfs identified by the space satellite {\it Gaia}, a revolution in the spectroscopic characterisation of white dwarfs is underway.
Merdeka Belajar Kampus Merdeka (MBKM) adalah program pembelajaran pendidikan tinggi yang mandiri dan serbaguna yang dirancang untuk menciptakan komunitas pembelajaran kreatif yang tidak membatasi yang memenuhi kebutuhan mahasiswa Penelitian ini bertujuan untuk untuk melihat dampak dan persepsi penerapan Merdeka Belajar Kampus Merdeka (MBKM) kepada seluruh mahasiswa di perguruan tinggi swasta dengan tujuan untuk melihat sejauh mana pemahaman dan persepsi mahasiswa dan dampak dari penerapan program Merdeka Belajar Kampus Merdeka (MBKM) yang ada di Perguruan Tinggi. Penelitian ini merupakan penelitian deskriptif dengan pendekatan kuantitatif dengan metode survei. Data diperoleh dari populasi yakni 96 responden yang merupakan mahasiswa Program Studi Pendidikan Biologi Universitas Flores. Data dikumpulkan melalui kuesioner. Teknik analisis data dimulai dari pengumpulan data kemudian dianalisis menggunakan analisis deskriptif. Hasil dari penelitian survei ini menunjukan bahwa mahasiswa pada program studi pendidikan biologi, Fakultas Keguruan dan Ilmu Pendidikan (FKIP) Universitas Flores memberikan respon yang positif terhadap program Merdeka Belajar Kampus Merdeka (MBKM).
V. Astro, E. Fiacco, Kelly J. Cardona-Londoño
et al.
Objective The transcriptional landscape of Klinefelter syndromeduring early embryogenesis remains elusive. This study aimed to evaluate the impact of X chromosome overdosage in 47,XXY males induced pluripotent stem cells (iPSCs) obtained from patients with different genomic backgrounds and ethnicities. Design and method We derived and characterized 15 iPSC lines from four Saudi 47,XXY KS patients and one Saudi 46,XY male. We performed a comparative transcriptional analysis using the Saudi KS-iPSCs and a cohort of European and North American KS-iPSCs. Results We identified a panel of X-linked and autosomal genes commonly dysregulated in Saudi and European/North American KS-iPSCs vs 46,XY controls. Our findings demonstrate that seven PAR1 and nine non-PAR escape genes are consistently dysregulated and mostly display comparable transcriptional levels in both groups. Finally, we focused on genes commonly dysregulated in both iPSC cohorts and identified several gene-ontology categories highly relevant to KS physiopathology, including aberrant cardiac muscle contractility, skeletal muscle defects, abnormal synaptic transmission, and behavioral alterations. Conclusions Our results indicate that a transcriptomic signature of X chromosome overdosage in KS is potentially attributable to a subset of X-linked genes sensitive to sex chromosome dosage and escaping X inactivation, regardless of the geographical area of origin, ethnicity, and genetic makeup.
We identify a new dust instability that occurs in warped discs. The instability is caused by the oscillatory gas motions induced by the warp in the bending wave regime. We first demonstrate the instability using a local 1D (vertical) toy model based on the warped shearing box coordinates and investigate the effects of the warp magnitude and dust Stokes number on the growth of the instability. We then run 3D SPH simulations and show that the instability is manifested globally by producing unique dust structures that do not correspond to gas pressure maxima. The 1D and SPH analysis suggest that the instability grows on dynamical timescales and hence is potentially significant for planet formation.
Neste trabalho iremos discutir os aspectos físicos principais referentes ao processo de criação de partículas perto do horizonte de eventos de um buraco negro. Para tanto, vamos examinar brevemente o formalismo da teoria quântica de campos em espaço-tempo curvo. Discutiremos sobre o porquê de se usar esta abordagem e como ela é utilizada para se estudar processos quânticos na vizinhança do horizonte de eventos de um buraco negro. Também apresentaremos resultados que revelam como buracos negros podem ser fundamentais na busca de uma teoria de gravitação quântica.
To report outcomes and risk factors of ultrahypofractionated (UHF) radiotherapy for Japanese prostate cancer patients. This multi-institutional retrospective analysis comprised 259 patients with localized prostate cancer from 6 hospitals. A total dose of 35–36 Gy in 4–5 fractions was prescribed for sequential or alternate-day administration. Biochemical failure was defined according to the Phoenix ASTRO consensus. Toxicities were assessed using National Cancer Institute Common Toxicity Criteria version 4. Tumor control and toxicity rates were analyzed by competing risk frames. Median follow-up duration was 32 months (range 22–97 months). 2- and 3-year biochemical control rates were 97.7% and 96.4%, respectively. Initial prostate-specific antigen (p < 0.01) and neoadjuvant androgen deprivation therapy (p < 0.05) were identified as risk factors for biochemical recurrence. 2- and 3-year cumulative ≥ Grade 2 late genitourinary (GU) toxicities were 5.8% and 7.4%, respectively. Corresponding rates of gastrointestinal (GI) toxicities were 3.9% and 4.5%, respectively. Grade 3 rates were lower than 1% for both GU and GI toxicities. No grade 4 or higher toxicities were encountered. Biologically effective dose was identified as a risk factor for ≥ Grade 2 late GU and GI toxicities (p < 0.05). UHF radiotherapy offered effective, safe treatment for Japanese prostate cancer with short-term follow-up. Our result suggest higher prescribed doses are related to higher toxicity rates.
QDaedalus is an automated, computer-controlled astro-geodetic measurement system. Astronomical deflections of the vertical measured by the QDaedalus system are significantly influenced by atmospheric refraction. Therefore, the measuring system was further improved by recording the environmental parameters influencing the refraction (air pressure, temperature, humidity) with accurate and high time resolution. In addition to meteorological parameters, refraction also depends on the spectrum of the stars. Both the continuously measured meteorological parameters and the color of the stars were taken into account in the calculation of the refraction. To control the method, we used the deflection of the vertical values of the Pistahegy point in the southern part of Budapest which were determined over 7 years during 260 night measurements. The corrected measurements fit within 0.01" with the average value of previous Pistahegy measurements. The standard deviation of the differences due to the corrections, however, may reach 0.015" for the DOV components.
We present an enhanced stochastic trust-region optimization with adaptive sampling (ASTRO-DF) in which optimizing an iteratively constructed local model on estimates of objective values with stochastic sample size guides the search. The noticeable feature is that the underdetermined quadratic model with a diagonal Hessian requires fewer function evaluations, which is particularly useful at high dimensions. This paper describes the enhanced algorithm in detail. It gives several theoretical results, including iteration complexity, and renders almost sure convergence guarantees. We report in our numerical experience the finite-time superiority of the enhanced ASTRO-DF over state-of-the-art using the SimOpt library.
Apresentamos uma tradução do inglês para o português brasileiro do importante artigo de Sir Robert Penrose sobre buracos negros, mais especificamente sobre a matemática da singularidade física.
The gravitational-wave candidate GW151216 is a proposed binary black hole event from the first observing run of the Advanced LIGO detectors. Not identified as a bona fide signal by the LIGO--Virgo collaboration, there is disagreement as to its authenticity, which is quantified by $p_\text{astro}$, the probability that the event is astrophysical in origin. Previous estimates of $p_\text{astro}$ from different groups range from 0.18 to 0.71, making it unclear whether this event should be included in population analyses, which typically require $p_\text{astro}>0.5$. Whether GW151216 is an astrophysical signal or not has implications for the population properties of stellar-mass black holes and hence the evolution of massive stars. Using the astrophysical odds, a Bayesian method which uses the signal coherence between detectors and a parameterised model of non-astrophysical detector noise, we find that $p_\text{astro}=0.03$, suggesting that GW151216 is unlikely to be a genuine signal. We also analyse GW150914 (the first gravitational-wave detection) and GW151012 (initially considered to be an ambiguous detection) and find $p_\text{astro}$ values of 1 and 0.997 respectively. We argue that the astrophysical odds presented here improve upon traditional methods for distinguishing signals from noise.
The European Space Agency's Solar Orbiter spacecraft will pass approximately downstream of the position of comet C/2019 Y4 (ATLAS) in late May and early June 2020. We predict that the spacecraft may encounter the comet's ion tail around 2020 May 31-June 1, and that the comet's dust tail may be crossed on 2020 June 6. We outline the solar wind features and dust grain collisions that the spacecraft's instruments may detect when crossing the comet's two tails. Solar Orbiter will also pass close to the orbital path of C/2020 F8 (SWAN) on 2020 May 22, but we believe that it is unlikely to detect any material associated with that comet.
Kushagra Upadhyay, Bhuwan Joshi, Prabir K. Mitra
et al.
This paper presents a detailed description of various subsystems of CALLISTO solar radio spectrograph installed at the USO/PRL. In the front-end system, a log periodic dipole antenna (LPDA) is designed for the frequency range of 40-900 MHz. In this paper LPDA design, its modifications, and simulation results are presented. We also present some initial observations taken by CALLISTO at Udaipur.
The kinetic energy of supersonic turbulence within interstellar clouds is subject to cooling by dissipation in shocks and subsequent line radiation. The clouds are therefore susceptible to a condensation process controlled by the specific entropy. In a form analogous to the thermodynamic entropy, the entropy for supersonic turbulence is proportional to the log of the product of the mean turbulent velocity and the size scale. We derive a dispersion relation for the growth of entropic instabilities in a spherical self-gravitating cloud and find that there is a critical maximum dissipation time scale, about equal to the crossing time, that allows for fragmentation and subsequent star formation. However, the time scale for the loss of turbulent energy may be shorter or longer, for example with rapid thermal cooling or the injection of mechanical energy. Differences in the time scale for energy loss in different star-forming regions may result in differences in the outcome, for example, in the initial mass function.
Context. Ground-based astro-geodetic observations and atmospheric radio occultations are two examples of observational techniques requiring a scrutiny analysis of atmospheric refraction. In both cases, the measured changes of the observables are geometrically related to changes in the photon path through the refractive profile of the crossed medium. Therefore, having a clear knowledge of how the refractivity governs the photon path evolution is of prime importance to clearly understand observational features. Aims. We analytically performed the integration of the photon path and the light time of rays traveling across a non-spherically symmetric planetary atmosphere. Methods. Assuming that the atmospheric refraction evolves linearly with the Newtonian potential, we derived an exact solution to the equations of geometrical optics. By varying the solution’s arbitrary constants of integration, we reformulated the equation of geometrical optics into a new set of osculating equations describing the constants’ evolution following any changes in the refractive profile. We have highlighted the capabilities of the formalism, carrying out five realistic applications in which we derived analytical expressions. Finally, we assessed the accuracy by comparing the solution to results from a numerical integration of the equations of geometrical optics in the presence of a quadrupolar moment (J2). Results. Analytical expressions for the light time and the refractive bending are given with relative errors at the level of one part in 108 and one part in 105, for typical values of the refractivity and J2 at levels of 10−4 and 10−2, respectively. Conclusions. The establishment of the osculating equations for the ray propagation has two main advantages. Firstly, it provides an easy and comprehensive geometrical picture for interpreting the photon path. Secondly, it allows the analytical solving of the ray propagation in the presence of non-radial dependencies in the refractive profile.
AIMS To report the long-term outcome of a single institution series of pure ductal carcinoma in situ (DCIS) treated with accelerated partial irradiation using intraoperative electrons (IOERT). METHODS From 2000 to 2010, 180 DCIS patients, treated with quadrantectomy and 21 Gy IOERT, were analyzed in terms of ipsilateral breast recurrences (IBRs) and survival outcomes by stratification in two subgroups. The low-risk group included patients who fulfilled the suitable definition according to American Society of Radiation Oncology (ASTRO) Guidelines (size ≤2.5 cm, grade 1-2 and surgical margins ≥3 mm) (Suitable), while the remaining ones formed the high-risk group (Non-Suitable). RESULTS Eighty-four and 96 patients formed the Suitable and Non-Suitable groups, respectively. In the whole population, the cumulative incidence of IBR at 5, 7 and 10 years was 19%, 21%, and 25%, respectively. In the Suitable group, the cumulative incidence of IBR remained constant at 11% throughout the years, while in the Non-Suitable group increased from 26% at 5 years to 36% at 10 years (p < 0.0001). When hormonal positivity and HER2 absence of expression were added to the selection of the Suitable group, the cumulative incidence of IBR dropped and stabilized at 4% at 10 years. None died of breast cancer. In the whole population, 5-year and 10-year overall survival rate was 98% and 96.5%, respectively, without any difference between the two groups. CONCLUSIONS The overall and by group IBR rates were high and stricter criteria are required for acceptable local control for Suitable DCIS. Because of the concerns raised, IOERT should not be used in clinical practice.
A photometric analysis and evolutionary stages of the contact binary V2790~Ori is presented. The $BVR_\mathrm{C}$ observations were carried out at the Thai National Observatory. The photometric light curves were fitted to provide fundamental parameters, required to use in the analysis of evolutionary stages of the binary. The results show that V2790~Ori is a W-type contact system with a mass ratio of $q$~=~2.932. The orbital period increase is found at a rate of $\mathrm{d}P\slash \mathrm{d}t~=~$1.03$\times10^{-7}~$d~yr$^{-1}$. It implies that a rate of mass transfer from the secondary component to the primary one is $\mathrm{d}m_2\slash \mathrm{d}t~=~$6.31$\times10^{-8}~M_{\odot}$~yr$^{-1}$. Furthermore, we find that from the detached phase to the contact phase, mass of the evolved secondary component has been lost 1.188$\pm$0.110~$\mathrm{M}_{\odot}$, i.e., mass lost by the system of 0.789$\pm$0.073~$\mathrm{M}_{\odot}$ and mass transfer to the primary of 0.399$\pm$0.037~$\mathrm{M}_{\odot}$. Since the time of the first overflow, the angular momentum loss is found to be 72.2~$\%$ of $J_\mathrm{FOF}$, causing the orbit and Roche surface to shrink until the present time.
The decomposition of the Solar system abundances of heavy isotopes into their s- and r- components plays a key role in our understanding of the corresponding nuclear processes and the physics and evolution of their astrophysical sites. We present a new method for determining the s- and r- components of the Solar system abundances, fully consistent with our current understanding of stellar nucleosynthesis and galactic chemical evolution. The method is based on a study of the evolution of the solar neighborhood with a state-of-the-art 1-zone model, using recent yields of low and intermediate mass stars as well as of massive rotating stars. We compare our results with previous studies and we provide tables with the isotopic and elemental contributions of the s- and r-processes to the Solar system composition.