Toward Massive Detection Of Planets Around M Dwarfs Using The Radial Velocity Technique
DOWNLOAD
Download Toward Massive Detection Of Planets Around M Dwarfs Using The Radial Velocity Technique PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Toward Massive Detection Of Planets Around M Dwarfs Using The Radial Velocity Technique book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Toward Massive Detection Of Planets Around M Dwarfs Using The Radial Velocity Technique
DOWNLOAD
Author : Ji Wang
language : en
Publisher:
Release Date : 2012
Toward Massive Detection Of Planets Around M Dwarfs Using The Radial Velocity Technique written by Ji Wang and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2012 with categories.
M dwarfs are the least massive but the most common type of stars in the solar neighborhood. Discoveries of M dwarf planets would lead to a complete understanding of planet formation and evolution around stars of different types. Radial velocity (RV) technique is one of the leading technologies that detect exoplanets and the RV technique favors detection of planet in the habitable zone of an M dwarf. The dispersed fixed delay interferometer (DFDI) method is one branch of the RV technique that uses an interferometer to boost Doppler sensitivity of a spectrograph with a given resolution. I systematically studied the comparison between the DFDI method and the traditional high-resolution spectrograph method (the DE method).
Exoplanet Science Strategy
DOWNLOAD
Author : National Academies of Sciences, Engineering, and Medicine
language : en
Publisher: National Academies Press
Release Date : 2019-01-17
Exoplanet Science Strategy written by National Academies of Sciences, Engineering, and Medicine and has been published by National Academies Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2019-01-17 with Science categories.
The past decade has delivered remarkable discoveries in the study of exoplanets. Hand-in-hand with these advances, a theoretical understanding of the myriad of processes that dictate the formation and evolution of planets has matured, spurred on by the avalanche of unexpected discoveries. Appreciation of the factors that make a planet hospitable to life has grown in sophistication, as has understanding of the context for biosignatures, the remotely detectable aspects of a planet's atmosphere or surface that reveal the presence of life. Exoplanet Science Strategy highlights strategic priorities for large, coordinated efforts that will support the scientific goals of the broad exoplanet science community. This report outlines a strategic plan that will answer lingering questions through a combination of large, ambitious community-supported efforts and support for diverse, creative, community-driven investigator research.
Externally Dispersed Interferometry For Terrestrial Exoplanet Detection
DOWNLOAD
Author : Philip Steven Muirhead
language : en
Publisher:
Release Date : 2011
Externally Dispersed Interferometry For Terrestrial Exoplanet Detection written by Philip Steven Muirhead and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2011 with categories.
Terrestrial exoplanets are observationally challenging to detect and characterize. Compared to gas giant exoplanets, terrestrial exoplanets introduce significantly smaller radial velocity signals and transit depths on their host stars. The signals are larger for terrestrial exoplanets orbiting M-dwarf stars, which have lower masses and radii than Sun-like F, G and K-type stars, and dominate stellar populations by number. Detecting exoplanets around M dwarfs is itself difficult because of their lower luminosities and lower flux at visible wavelengths, where most radial velocity and transit exoplanet surveys operate. I present here the motivation, development and results from a radial velocity program conducted on M dwarfs using near-infrared wavelengths, where M dwarf spectra peak in flux. To achieve high radial-velocity precision, I have used a technique called externally dispersed interferometry. It involves the combination of an interferometer and a moderate-resolution spectrograph on the 200 inch (5.1 m) Hale Telescope at Palomar Observatory. The TripleSpec Exoplanet Discovery Instrument, or TEDI, is the first such instrument to operate at nearinfrared wavelengths. Our results indicate that contamination by narrow absorption lines introduced by the Earth's atmosphere limit radial velocity performance to that which can detect gas giant planets. I have conducted a survey of nearby M dwarfs, and can rule out with 3[sigma] confidence the presence of short-period gas giant planets in circular orbits around a few nearby M dwarfs. The results of this experiment direct future extrasolar planet instrumentation toward spectral regions with little telluric contamination and with higher resolution, to detect terrestrial exoplanets orbiting M dwarfs.
Developing New Tools And Techniques To Probe The M Dwarf Planet Population
DOWNLOAD
Author : Shubham Kanodia
language : en
Publisher:
Release Date : 2022
Developing New Tools And Techniques To Probe The M Dwarf Planet Population written by Shubham Kanodia and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2022 with categories.
We do not understand the largest planets around the smallest and most numerous stars in the Galaxy. M dwarfs are the most common type of stars in the Galaxy. Empirical studies show that they also play host to more inner planets than FGK stars, despite this, of the currently $\sim 5000$ confirmed exoplanets, only about 250 orbit M dwarfs, of which only $\sim 65$ have precise mass and radii measurements! The population of planets around M dwarfs is poorly understood. In this thesis I will discuss our efforts to detect and obtain precise measurements for planets around M dwarfs, and then to place this sample of M dwarfs in context of the larger sample of planets around FGK stars. The first part of my dissertation focusses on the instrumentation efforts for the Habitable zone Planet Finder (HPF), and NEID. HPF is a stabilized near-infrared (NIR) fiber-fed radial velocity (RV) spectrograph at the 10 m Hobby Eberly Telescope (HET) at McDonald Observatory, Texas, USA, while NEID is a new high-precision spectrograph in the red-optical installed at the 3.5 m WIYN telescope at Kitt Peak, Arizona, USA. I was in charge of developing, integrating and testing the fiber-feed for HPF, as well as the optical simulations to verify the alignment of the instrument. For NEID, not only did I lead a similar effort for the fiber-feed and simulations, but was also responsible for the chromatic exposure meter which is essential to measure exposure midpoints for barycentric corrections. In conjunction, I developed the algorithm for performing these corrections, which are now used in HPF, NEID and numerous other RV spectrographs. HPF with its large aperture and near-infrared bandpass, and NEID with its red-optical coverage have already started to enable the RV follow up of planets around mid-to-late and early M dwarfs respectively. I then discuss some results from the HPF RV survey, where first I test the scrambling performance of HPF on the fixed altitude HET using on-sky data on an M dwarf. Then I present the results of a serendipitous observation of a flare around the ultracool dwarf vB 10. The HPF spectra taken during the flare show a red excess in the He 10830 \AA~triplet which is similar to observations of coronal rain for the Sun, while also placing a limit on the atmospheric mass loss from flares for planets orbiting such stars. Alongside the instrumentation and observational efforts, I also built upon a nonparametric framework to model exoplanet masses and radii (M-R), which was then applied to a sample of planets around M dwarfs. By comparing the results for M dwarf planets with those from FGK stars we notice some systemic differences in their distributions. However, further inferences were deterred by the small sample of transiting M dwarf planets with mass measurements. I then discuss the efforts to use HPF and NEID to follow up on M dwarf planet candidates discovered by TESS. Not only do these planets help fill in the M-R plane for M dwarfs, but also highlight interesting correlations with stellar properties. Finally, I conclude by giving an overview of how my work on instrumentation, algorithms and novel statistical frameworks has helped develop our understanding of the M dwarf planet population. The ongoing transiting gas giant follow-up will be continued in the future, which will help us shed further light on how these giant planets form around the smallest stars.
The Exoplanet Handbook
DOWNLOAD
Author : Michael Perryman
language : en
Publisher: Cambridge University Press
Release Date : 2018-08-30
The Exoplanet Handbook written by Michael Perryman and has been published by Cambridge University Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2018-08-30 with Science categories.
A complete and in-depth review of exoplanet research, covering the discovery methods, physics and theoretical background.
High Throughput Interferometric Doppler Technique For Planet Detection
DOWNLOAD
Author : Suvrath Mahadevan
language : en
Publisher:
Release Date : 2006
High Throughput Interferometric Doppler Technique For Planet Detection written by Suvrath Mahadevan and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2006 with categories.
ABSTRACT: We have developed a novel instrument called the Exoplanet Tracker (ET) that can measure precise differential radial velocities, as well as barycentric radial velocities. ET is installed at the Kitt Peak 2.1 meter telescope and uses a Michelson interferometer in series with a medium resolution spectrograph. This instrument allows stellar radial velocities to be measured precisely without the use of a high resolution spectrograph. This allows the instrument to be very efficient in collecting light from the telescope. ET can achieve a radial velocity precision of 5-10 m s−1 over a 10 day observing run. A survey for extrasolar planets using the ET instrument has led to the detection of radial velocity variability for the star HD102195. Using photometry, CaII HK measurements, and precision radial velocities we demonstrate that these radial velocity variations are caused by a giant planet in a 4.11 day orbit around HD102195. A prototype monolithic interferometer has also been built for the ET instrument and is capable of delivering precise radial velocities. A large multi-object radial velocity instrument based on the ET instrument has been built and installed at the wide field Sloan 2.5 m telescope. This instrument, called the W.M. Keck Exoplanet Tracker, is capable of obtaining precise radial velocities for 59 stars simultaneously. Over the next few years this multi-object instrument will be used to conduct an All Sky ExoPlanet Survey capable of efficiently searching thousands of stars for planets.
Transiting Exoplanets
DOWNLOAD
Author : Carole A. Haswell
language : en
Publisher: Cambridge University Press
Release Date : 2010-07-29
Transiting Exoplanets written by Carole A. Haswell and has been published by Cambridge University Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2010-07-29 with Science categories.
The methods used in the detection and characterisation of exoplanets are presented in this unique textbook for advanced undergraduates.
Planetary Astrobiology
DOWNLOAD
Author : Victoria Meadows
language : en
Publisher: University of Arizona Press
Release Date : 2020-07-07
Planetary Astrobiology written by Victoria Meadows and has been published by University of Arizona Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2020-07-07 with Science categories.
Are we alone in the universe? How did life arise on our planet? How do we search for life beyond Earth? These profound questions excite and intrigue broad cross sections of science and society. Answering these questions is the province of the emerging, strongly interdisciplinary field of astrobiology. Life is inextricably tied to the formation, chemistry, and evolution of its host world, and multidisciplinary studies of solar system worlds can provide key insights into processes that govern planetary habitability, informing the search for life in our solar system and beyond. Planetary Astrobiology brings together current knowledge across astronomy, biology, geology, physics, chemistry, and related fields, and considers the synergies between studies of solar systems and exoplanets to identify the path needed to advance the exploration of these profound questions. Planetary Astrobiology represents the combined efforts of more than seventy-five international experts consolidated into twenty chapters and provides an accessible, interdisciplinary gateway for new students and seasoned researchers who wish to learn more about this expanding field. Readers are brought to the frontiers of knowledge in astrobiology via results from the exploration of our own solar system and exoplanetary systems. The overarching goal of Planetary Astrobiology is to enhance and broaden the development of an interdisciplinary approach across the astrobiology, planetary science, and exoplanet communities, enabling a new era of comparative planetology that encompasses conditions and processes for the emergence, evolution, and detection of life.
Astronomical Applications Of Astrometry
DOWNLOAD
Author : M. A. C. Perryman
language : en
Publisher: Cambridge University Press
Release Date : 2009
Astronomical Applications Of Astrometry written by M. A. C. Perryman and has been published by Cambridge University Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2009 with Nature categories.
An authoritative account of the contributions to science made by the Hipparcos satellite, for astronomers, astrophysicists and cosmologists.
Subtracting Stellar Signals And Improving Instrumentation On A Road Towards Other Earths
DOWNLOAD
Author : Matthew J. Giguere
language : en
Publisher:
Release Date : 2019
Subtracting Stellar Signals And Improving Instrumentation On A Road Towards Other Earths written by Matthew J. Giguere and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2019 with Astronomical spectroscopy categories.
Improvements in radial velocity precision and detection capabilities will one day lead to the detection of earth-mass planets orbiting in the habitable zones of nearby stars. Detecting low mass planets at large separations will help fill in our understanding of how planetary systems form and subsequently evolve. Additionally, they will provide a target list for followup with future facilities such as the James Webb Space Telescope that will search for atmospheric biosignatures and help determine how common life is in the universe. This thesis presents observations, methods, and analyses created to improve the instrumental precision, efficiency, and detection capabilities of the radial velocity (RV) method of exoplanet detection. Chapters 2 and 3 present 7 planetary systems discovered using the HIRES Spectrograph on the Keck I telescope. One of these systems presents a challenge for theorists, as it cannot be explained with current planet formation and migration theories. We also detect a correlation between RV measurements and S-value measurements, which are an indicator of stellar activity. By linearly modeling and removing this correlation, the residual RMS of the velocities improved by 21%. In Chapters 4 and 5 we describe the commissioning and software stack behind CHIRON, a new instrument we commissioned on a 1.5 m telescope at the CTIO Observatory. CHIRON provides a queue-based observing system for the general astronomical community, and dealing manually with the large amount of data collected nightly quickly became an overwhelming task. Primarily to reduce time and error, most of the observing pipeline for CHIRON was automated, which is described in these two chapters. Lastly, we present observations from a multi-facility campaign to simultaneously observe the young and moderately active K dwarf e Eridani. We use this data to explore three methods of modeling stellar activity: spot modeling, the FF' method, and a new approach that makes use of Ha measurements input into the FF' method, which we refer to as the HH' method. Spot modeling yielded the best result of the three methods tested in terms of residual RMS after subtracting the model from the data, and reduced the RMS from 7.4 m s -1 to 2.7 m s-1. However, the HH' method benefits from not needing precise space-based photometry as input. Additionally, the HH' method only makes use of one of the thousands of lines in the visible spectrum; incorporating more spectral lines into the model would most likely lead to significant improvements.