English
Related papers

Related papers: The DDO IVC Distance Project

200 papers

Molecular clouds (MC) are structures of dense gas in the interstellar medium (ISM), that extend from ten to a few hundred parsecs and form the main gas reservoir available for star formation. Hydrodynamical simulations of varying complexity…

We found that an intermediate velocity cloud (IVC) IVC 86-36 in HI 21 cm emission shows a head-tail distribution toward the Galactic plane with marked parallel filamentary streamers, which is extended over 40 degrees in the sky. The…

The investigation of the statistical properties of maps of line centroids has been used for almost 50 years, but there is still no general agreement on their interpretation. We try to quantify which properties of underlying turbulent…

Astrophysics · Physics 2009-11-11 V. Ossenkopf , A. Esquivel , A. Lazarian , J. Stutzki

We present high resolution (R = 60,000) measurements of the NaI D1 and D2 (5890 A) and CaII K (3933 A) interstellar absorption line profiles recorded towards several post-AGB stars located within the M13 and M15 globular clusters,…

Astrophysics of Galaxies · Physics 2015-05-13 B. Y. Welsh , J. M. Wheatley , R. Lallement

H$_{\rm I}$ 21-cm and $^{12}$CO 2.6-mm line emissions respectively trace the atomic and molecular gas phases, but they miss most of the opaque H$_{\rm I}$ and diffuse H$_2$ present in the Dark Neutral Medium (DNM) at the transition between…

High Energy Astrophysical Phenomena · Physics 2018-03-28 Q. Remy , I. A. Grenier , D. J. Marshall , J. M. Casandjian

The outer Galaxy presents an optimal setting for investigating molecular clouds and star formation in environments with low metallicity. A total of 72 Galactic edge clouds were surveyed using the CO\,(2--1) line with the IRAM\,30\,m…

Context. Infrared dark clouds (IRDCs) are ubiquitous in the Milky Way, yet they play a crucial role in breeding newly-formed stars. Aims. With the aim of further understanding the dynamics, chemistry, and evolution of IRDCs, we carried out…

Astrophysics of Galaxies · Physics 2017-02-08 Chuan-Peng Zhang , Jing-Hua Yuan , Guang-Xing Li , Jian-Jun Zhou , Jun-Jie Wang

The diffuse gas in and nearby the Milky Way plays an important role in the evolution of the entire Galaxy. It has a complex structure characterized by neutral, weakly and highly ionized gas, dust, and molecules. We probe this gas through…

Astrophysics of Galaxies · Physics 2013-02-19 C. Pinto , G. A. Kriss , J. S. Kaastra , E. Costantini , J. Ebrero , K. C. Steenbrugge , M. Mehdipour , G. Ponti

Many mobile robots rely on 2D laser scanners for localization, mapping, and navigation. However, those sensors are unable to correctly provide distance to obstacles such as glass panels and tables whose actual occupancy is invisible at the…

Robotics · Computer Science 2019-03-12 Jens Lundell , Francesco Verdoja , Ville Kyrki

Galactic interstellar dust (ISD) is the major ingredient in planetary formation. However, information on this important material has been extremely limited. Recently the Ulysses dust detector has identified and measured interstellar dust…

High-Velocity Clouds (HVCs) have radial velocities that cannot be explained by the global Galactic rotation; their distances remain mostly unknown, and their true nature and origin are still a mystery. Some of them could be of galactic…

Astrophysics · Physics 2007-05-23 F. Combes , V. Charmandaris

Interstellar objects (ISOs) represent a compelling and under-explored category of celestial bodies, providing physical laboratories to understand the formation of our solar system and probe the composition and properties of material formed…

Accurate velocity estimation of surrounding moving objects and their trajectories are critical elements of perception systems in Automated/Autonomous Vehicles (AVs) with a direct impact on their safety. These are non-trivial problems due to…

Robotics · Computer Science 2024-03-27 MReza Alipour Sormoli , Mehrdad Dianati , Sajjad Mozaffari , Roger woodman

Study of pre-stellar cloud evolution requires observations with high sensitivity and resolution, and regions of high-mass star formation are particularly challenging. We wish to quantify, to what accuracy the physical conditions within a…

Astrophysics of Galaxies · Physics 2022-10-12 M. Juvela , E. Mannfors , T. Liu , L. V. Toth

Diffuse interstellar bands (DIBs) hold a lot of information about the state and the structure of the ISM. Structure can most directly be observed by extensive spectroscopic surveys, including surveys of stars where DIBs are especially…

Astrophysics of Galaxies · Physics 2017-05-10 Janez Kos

Estimates of galaxy distances based on indicators that are independent of cosmological redshift are fundamental to astrophysics. Researchers use them to establish the extragalactic distance scale, to underpin estimates of the Hubble…

The rise of synoptic sky surveys has ushered in an era of big data in time-domain astronomy, making data science and machine learning essential tools for studying celestial objects. While tree-based models (e.g. Random Forests) and deep…

Instrumentation and Methods for Astrophysics · Physics 2024-07-26 Siddharth Chaini , Ashish Mahabal , Ajit Kembhavi , Federica B. Bianco

We present a new distance determination to the Large and Small Magellanic Clouds using the newly developed red clump stars method (Paczynski and Stanek 1998). This new, single-step, Hipparcos calibrated method seems to be one of the most…

Astrophysics · Physics 2007-05-23 A. Udalski , M. Szymanski , M. Kubiak , G. Pietrzynski , P. Wozniak , K. Zebrun

Under very general assumptions of metric theory of spacetime, photons traveling along null geodesics and photon number conservation, two observable concepts of cosmic distance, i.e. the angular diameter and the luminosity distances are…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-16 Kai Liao , Zhengxiang Li , Shuo Cao , Marek Biesiada , Xiaogang Zheng , Zong-Hong Zhu

To evaluate clustering results is a significant part of cluster analysis. Since there are no true class labels for clustering in typical unsupervised learning, many internal cluster validity indices (CVIs), which use predicted labels and…

Machine Learning · Computer Science 2021-06-21 Shuyue Guan , Murray Loew