DOCSLIB.ORG

Science 1. Council of Scientific and Industrial Research

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Science 1. Council of Scientific and Industrial Research Current Affairs - March 2020 to May 2020 Month May 2020 Type Science and Technology 113 Current Affairs were found in Last Three Months for Type - Science and Technology Science 1. Council of Scientific and Industrial Research along with National Physical Laboratory recently discovered a bi-luminescent security ink, to be used to counterfeit currency notes. It shows two colours when exposed to light. Ink is produced by mixing two different colours namely green and red in the ratio 3:1. This mixture was hated to 400-degree Celsius. 2. Scientists from Institute of Advanced Study in Science and Technology (IASST) developed a pH-responsive smart bandage that can deliver medicine applied in wound at pH that is suitable for the wound. It is developed by fabricating a nanotechnology-based cotton patch that uses cheap and sustainable materials like cotton and jute. Jute has been used for first time as a precursor in synthesizing fluorescent carbon dots, and water was used as dispersion medium. Stimuli-responsive nature of fabricated hybrid cotton patch acts as an advantage as in case of growth of bacterial infections in a wound, and this induces release of drug at lower pH which is favourable under these conditions. This pH-responsive behaviour of the fabricated cotton patch lies in the unique behaviour of the jute carbon dots incorporated in the system because of the different molecular linkages formed during the carbon dot preparation. Use of cheap and sustainable material like cotton and jute to fabricate patch makes whole process biocompatible, non-toxic, low cost and sustainable. 3. Scientists at Hyderabad-based DNA Finger Printing and Diagnostics Center have discovered a new mechanism that prevents cancer when an anti-cancer protein is converted. CDFD scientists have identified a rare p53 form of tongue cancer in Indians, which causes these mutant p53 cancers. Scientists identified genes of mutant p53 protein. One of these genes, called SMARCD1, is the most important. SMARCD1 converts a protein into symbolic words. It goes with other proteins and forms a multi-protein complex. Scientists have found that SMARCD-1 is seen in tongue cancer in Indians. 4. IIT BHU Researchers made significant achievements in developing nanomaterials based supercapacitors to achieve high energy density and power density of supercapacitors. High energy density of supercapacitors suggests that constant current can be withdrawn for longer duration without recharging. Hence automobiles can run longer distances without charging. Researchers developed a cost-effective process of producing reduced graphene oxide (rGO) at a moderate temperature of 100°C, with high capacitance performance. Researchers also developed a novel green approach for synthesis of Iron-based nanocatalyst, which can be used for large scale production of Cabon Nanotubes. Additionally, Group is working on optoelectronic applications of nanomaterials, for developing novel nanostructures of carbon and metal dichalcogenides semiconductors for photodetection and Surface-Enhanced Raman spectroscopy (SERS). SERS can help detect harmful molecules present in water at ultra-low concentrations. They demonstrated detection of Rhodamine 6G (R6G), an organic laser dye up to lowest limit of sub-nano-molar concentration using rGO and MoS2 nanomaterials. 5. Scientists at Agharkar Research Institute Pune come up with plant data of the Northern Western Ghats, which indicates that plateaus, in addition to forests, should be prioritized for conservation of Northern Western Ghats. They found that majority of endemic species are therophytes, which complete their life cycle in a short period during monsoon. Northern Western Ghats have plateaus and cliffs that display maximum endemic species, unlike forests. Forests of Northern Western Ghats harbour many species which are not endemic. 6. Scientists at Sree Chitra Tirunal Institute for Medical Sciences and Technology (SCTIMST) developed a highly efficient superabsorbent material for liquid respiratory and other body fluid solidification and disinfection for the safe management of infected respiratory secretion, titled Chitra Acrylosorb Secretion Solidification System. AcryloSorb can absorb liquids at least 20 times more than its dry weight and also contains a decontaminant for in situ disinfection. 7. Scientists at Institute of Nano Science and Technology Mohali (INST) found a low-cost metal-free nanomaterial for visible light microbial disinfection which can be an alternative to silver and other metal-based materials - Researchers tested carbon nitride quantum dots (g-CNQDs) for visible-light-driven antibacterial activity and found it to be efficient, apart from being biocompatible with mammalian cells. It is a suggested anti bacterial alternative to metal/non-metal semiconductors and expensive silver, thus making it cost-effective 8. Scientists from Wadia Institute of Himalayan Geology Dehradun found a seasonal advancement in 220 surge-type glaciers in the Karakoram Range of Ladakh. ‘Surging’ glaciers are those that have shown advancement in volume and length over time. Behaviour of these glaciers, which are 40% of glaciated area of Karakoram, goes against normal trend of considerable reduction in volume and length of most glaciers in the Himalaya in recent decades. Surging of glaciers is potentially catastrophic as it can lead to destruction of villages, roads and bridges. It can also advance across a river valley and form ice-dammed lake. Scientists focused on Shispare and Muchuhar glaciers, former tributaries of once larger Hasanabad Glacier situated in Hunza Valley, Gilgit-Baltistan, Pakistan. Surge-type glaciers oscillate between brief (months to years) rapid flow and lengthy (tens to hundreds of years) slow flow or stagnation, which are called ‘active’ (or ‘surge’) and ‘quiescent’ phases, respectively. The study will help to understand diversity of glacial behaviour and help make accurate assessments of individual glacier mass balances for disaster planning and management. 9. Scientists from Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) fabricated an economical and energy-efficient wafer-scale photodetector (thin slice-based) using gold – silicon interface, for security applications. It could help detect weak scattered light as an indication of unwanted activity. Photodetectors are utmost important in ay optoelectronic circuit, used in wide variety of applications. However, material cost and intricate fabrication processes involved in realizing high-performance detectors make them unaffordable for day to day applications. The current invention provides a cost-effective solution-based fabrication method for high-performance photodetector. Detector exhibits a rapid response of 40 microseconds and can detect low light intensities. It operates in self-powered mode, wich high precision. 10. SpaceX became first private rocket company to send astronauts to space, launching NASA Astronauts Doug Hurley and Bob Behnken. It will end reliance of NASA on Russian space rockets for sending NASA astronauts to space. As part of mission, Astronauts in SpaceX's Crew Dragon Capsule entered International Space Station (ISS). 11. A new parasitic fungus has been discovered by a University of Copenhagen (Denmark) biologist, termed as Troglomyces twitteri. It is named after Twitter as it was discovered in Twitter. The image was posted in Twitter by an entomologist 1n 2018. The Fungi belongs to the order called Laboulbeniales. These are fungi that attack millipedes and insects. They look like larvae. 12. A new trough collector equipped with enhanced energy to serve industries has been developed by IIT Madras. The Parabolic Trough Collector is a lightweight and low-cost system with high energy efficiency and can operate under the country's varied climatic conditions. It can pave way for sustainable energy solutions in agriculture and industrial process heat sectors. Trough Collector focuses sunlight on a small area where it is absorbed and then utilised for heating and subsequently into energy generation. 13. A tiny near-Earth asteroid and temporary satellite of Earth named 2020 CD3, has been discovered, as part of the Mount Lemmon Survey or Catalina Sky Survey. It is the second temporary satellite of Earth discovered, after 2006 RH120, which was discovered in 2006. 2020 CD3 may have been captured by Earth around 2016–2017, and is expected to remain in a geocentric orbit around Earth until April 2020. Also, Astronomy student from University of British Columbia, Michelle Kunimoto discovered 17 new planets, including a potentially habitable Earth-sized rocky body that may have liquid water, by combing data collected by NASA’s Kepler Space Telescope. Finding also includes planet named ‘KIC-7340288 b’ which is 1000 light years away from eart and is one and a half times size of Earth and is in habitable zone of its star. 14. An analysis of 369 solar-like stars shows that brightness variations of our Sun are extremely weak by cosmic standards, making Sun extraordinarily monotonous. Study is led by Germany's Max Planck Institute for Solar System Research. For the first time, scientists compared Sun with hundreds of other stars with similar rotation periods and other fundamental properties. Study found that on average, other stars had five times more brightness variability than our sun. Sun is made up mainly of hydrogen and helium, formed more than 4.5 billion years ago. It stretches about 1.4 million kilometers across and has a surface temperature of 5,500 degrees
Load more

Recommended publications
  • Arxiv:2007.10995V1
    Draft version July 23, 2020 Typeset using LATEX twocolumn style in AASTeX63 Transits of Known Planets Orbiting a Naked-Eye Star Stephen R. Kane,1 Selc¸uk Yalc¸ınkaya,2 Hugh P. Osborn,3,4,5 Paul A. Dalba,1, ∗ Louise D. Nielsen,6 Andrew Vanderburg,7, † Teo Mocnikˇ ,1 Natalie R. Hinkel,8 Colby Ostberg,1 Ekrem Murat Esmer,9 Stephane´ Udry,6 Tara Fetherolf,1 Ozg¨ ur¨ Bas¸turk¨ ,9 George R. Ricker,4 Roland Vanderspek,4 David W. Latham,10 Sara Seager,4,11,12 Joshua N. Winn,13 Jon M. Jenkins,14 Romain Allart,6 Jeremy Bailey,15 Jacob L. Bean,16 Francois Bouchy,6 R. Paul Butler,17 Tiago L. Campante,18,19 Brad D. Carter,20 Tansu Daylan,4, ‡ Magali Deleuil,3 Rodrigo F. Diaz,21 Xavier Dumusque,6 David Ehrenreich,6 Jonathan Horner,20 Andrew W. Howard,22 Howard Isaacson,23,20 Hugh R.A. Jones,24 Martti H. Kristiansen,25,26 Christophe Lovis,6 Geoffrey W. Marcy,23 Maxime Marmier,6 Simon J. O’Toole,27,28 Francesco Pepe,6 Darin Ragozzine,29 Damien Segransan,´ 6 C.G. Tinney,30 Margaret C. Turnbull,31 Robert A. Wittenmyer,20 Duncan J. Wright,20 and Jason T. Wright32 1Department of Earth and Planetary Sciences, University of California, Riverside, CA 92521, USA 2Ankara University, Graduate School of Natural and Applied Sciences, Department of Astronomy and Space Sciences, Tandogan, TR-06100, Turkey 3Aix-Marseille Universit, CNRS, CNES, Laboratoire d’Astrophysique de Marseille, France 4Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 5NCCR/PlanetS, Centre for Space & Habitability, University of Bern, Bern, Switzerland 6Observatoire de Gen`eve, Universit´ede Gen`eve, 51 ch.
    [Show full text]
  • Sirius Astronomer Newsletter
    SIRIUS ASTRONOMER www.ocastronomers.org The Newsletter of the Orange County Astronomers April 2020 Free to members, subscriptions $12 for 12 issues Volume 47, Number 4 The large galaxy is NGC7331 and shown just to its left are 5 galaxies collectively referred to as the Deer Lick Group. Image by Dave Radosevich and Don Lynn, taken at our Anza site in multiple sessions during 2006 and 2008. It was captured through an 8 inch Maksutov telescope using an SBIG ST8 camera. From the Orange County Astronomers’ Board of Trustees: Response to COVID-19 Crisis The OCA Board of Trustees discussed our best course of action for upcoming events at its March 22, 2020 meeting, including Outreaches, General Meetings, SIG Meetings, Star Parties and all other in-person club events. We are cancelling all of these club events through the end of May, 2020 to help reduce exposure to the COVID-19 virus and in response to the orders from Governor Newsom and the state Health Department. Chapman University has cancelled our meetings through the end of May as part of its response to the crisis, so these general meetings could not go forward there anyway. We are exploring the possibility of holding at least part of our April and May meetings online, particularly the guest lectures. The details will be posted to the website, email groups and social media when they become available. Please check the OCA website periodically for updates, as the information should be posted there first. Star parties are now cancelled through the end of May. This includes both the Anza Star Parties and Orange County star parties.
    [Show full text]
  • Characterization of Temporarily Captured Minimoon 2020 CD₃ By
    Draft version August 13, 2020 Typeset using LATEX preprint style in AASTeX62 Characterization of Temporarily-Captured Minimoon 2020 CD3 by Keck Time-resolved Spectrophotometry Bryce T. Bolin,1, 2 Christoffer Fremling,1 Timothy R. Holt,3, 4 Matthew J. Hankins,1 Tomas´ Ahumada,5 Shreya Anand,6 Varun Bhalerao,7 Kevin B. Burdge,1 Chris M. Copperwheat,8 Michael Coughlin,9 Kunal P. Deshmukh,10 Kishalay De,1 Mansi M. Kasliwal,1 Alessandro Morbidelli,11 Josiah N. Purdum,12 Robert Quimby,12, 13 Dennis Bodewits,14 Chan-Kao Chang,15 Wing-Huen Ip,15 Chen-Yen Hsu,15 Russ R. Laher,2 Zhong-Yi Lin,15 Carey M. Lisse,16 Frank J. Masci,2 Chow-Choong Ngeow,15 Hanjie Tan,15 Chengxing Zhai,17 Rick Burruss,18 Richard Dekany,18 Alexandre Delacroix,18 Dmitry A. Duev,6 Matthew Graham,1 David Hale,18 Shrinivas R. Kulkarni,1 Thomas Kupfer,19 Ashish Mahabal,1, 20 Przemyslaw J. Mroz,´ 1 James D. Neill,1 Reed Riddle,21 Hector Rodriguez,22 Roger M. Smith,21 Maayane T. Soumagnac,23, 24 Richard Walters,1 Lin Yan,1 and Jeffry Zolkower18 1Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, U.S.A. 2IPAC, Mail Code 100-22, Caltech, 1200 E. California Blvd., Pasadena, CA 91125, USA 3University of Southern Queensland, Computational Engineering and Science Research Centre, Queensland, Australia 4Southwest Research Institute, Department of Space Studies, Boulder, CO-80302, USA 5Department of Astronomy, University of Maryland, College Park, MD 20742, USA 6Division of Physics, Mathematics and Astronomy, California Institute of
    [Show full text]
  • Exoplanet Exploration Collaboration Initiative TP Exoplanets Final Report
    EXO Exoplanet Exploration Collaboration Initiative TP Exoplanets Final Report Ca Ca Ca H Ca Fe Fe Fe H Fe Mg Fe Na O2 H O2 The cover shows the transit of an Earth like planet passing in front of a Sun like star. When a planet transits its star in this way, it is possible to see through its thin layer of atmosphere and measure its spectrum. The lines at the bottom of the page show the absorption spectrum of the Earth in front of the Sun, the signature of life as we know it. Seeing our Earth as just one possibly habitable planet among many billions fundamentally changes the perception of our place among the stars. "The 2014 Space Studies Program of the International Space University was hosted by the École de technologie supérieure (ÉTS) and the École des Hautes études commerciales (HEC), Montréal, Québec, Canada." While all care has been taken in the preparation of this report, ISU does not take any responsibility for the accuracy of its content. Electronic copies of the Final Report and the Executive Summary can be downloaded from the ISU Library website at http://isulibrary.isunet.edu/ International Space University Strasbourg Central Campus Parc d’Innovation 1 rue Jean-Dominique Cassini 67400 Illkirch-Graffenstaden Tel +33 (0)3 88 65 54 30 Fax +33 (0)3 88 65 54 47 e-mail: [email protected] website: www.isunet.edu France Unless otherwise credited, figures and images were created by TP Exoplanets. Exoplanets Final Report Page i ACKNOWLEDGEMENTS The International Space University Summer Session Program 2014 and the work on the
    [Show full text]
  • PT-365-Science-And-Tech-2020.Pdf
    SCIENCE AND TECHNOLOGY Table of Contents 1. BIOTECHNOLOGY ___________________ 3 3.11. RFID ___________________________ 29 1.1. DNA Technology (Use & Application) 3.12. Miscellaneous ___________________ 29 Regulation Bill ________________________ 3 4. DEFENCE TECHNOLOGY _____________ 32 1.2. National Guidelines for Gene Therapy __ 3 4.1. Missiles _________________________ 32 1.3. MANAV: Human Atlas Initiative _______ 5 4.2. Submarine and Ships _______________ 33 1.4. Genome India Project _______________ 6 4.3. Aircrafts and Helicopters ____________ 34 1.5. GM Crops _________________________ 6 4.4. Other weapons system _____________ 35 1.5.1. Golden Rice ________________________ 7 4.5. Space Weaponisation ______________ 36 2. SPACE TECHNOLOGY ________________ 8 4.6. Drone Regulation __________________ 37 2.1. ISRO _____________________________ 8 2.1.1. Gaganyaan _________________________ 8 4.7. Other important news ______________ 38 2.1.2. Chandrayaan 2 _____________________ 9 2.1.3. Geotail ___________________________ 10 5. HEALTH _________________________ 39 2.1.4. NaVIC ____________________________ 11 5.1. Viral diseases _____________________ 39 2.1.5. GSAT-30 __________________________ 12 5.1.1. Polio _____________________________ 39 2.1.6. GEMINI __________________________ 12 5.1.2. New HIV Subtype Found by Genetic 2.1.7. Indian Data Relay Satellite System (IDRSS) Sequencing _____________________________ 40 ______________________________________ 13 5.1.3. Other viral Diseases _________________ 40 2.1.8. Cartosat-3 ________________________ 13 2.1.9. RISAT-2BR1 _______________________ 14 5.2. Bacterial Diseases _________________ 40 2.1.10. Newspace India ___________________ 14 5.2.1. Tuberculosis _______________________ 40 2.1.11. Other ISRO Missions _______________ 14 5.2.1.1. Global Fund for AIDS, TB and Malaria42 5.2.2.
    [Show full text]
  • Arxiv:2001.10147V1
    Magnetic fields in isolated and interacting white dwarfs Lilia Ferrario1 and Dayal Wickramasinghe2 Mathematical Sciences Institute, The Australian National University, Canberra, ACT 2601, Australia Adela Kawka3 International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6102, Australia Abstract The magnetic white dwarfs (MWDs) are found either isolated or in inter- acting binaries. The isolated MWDs divide into two groups: a high field group (105 − 109 G) comprising some 13 ± 4% of all white dwarfs (WDs), and a low field group (B < 105 G) whose incidence is currently under investigation. The situation may be similar in magnetic binaries because the bright accretion discs in low field systems hide the photosphere of their WDs thus preventing the study of their magnetic fields’ strength and structure. Considerable research has been devoted to the vexed question on the origin of magnetic fields. One hypothesis is that WD magnetic fields are of fossil origin, that is, their progenitors are the magnetic main-sequence Ap/Bp stars and magnetic flux is conserved during their evolution. The other hypothesis is that magnetic fields arise from binary interaction, through differential rotation, during common envelope evolution. If the two stars merge the end product is a single high-field MWD. If close binaries survive and the primary develops a strong field, they may later evolve into the arXiv:2001.10147v1 [astro-ph.SR] 28 Jan 2020 magnetic cataclysmic variables (MCVs). The recently discovered population of hot, carbon-rich WDs exhibiting an incidence of magnetism of up to about 70% and a variability from a few minutes to a couple of days may support the [email protected] [email protected] [email protected] Preprint submitted to Journal of LATEX Templates January 29, 2020 merging binary hypothesis.
    [Show full text]
  • PLANETARY CANDIDATES OBSERVED by Kepler. VIII. a FULLY AUTOMATED CATALOG with MEASURED COMPLETENESS and RELIABILITY BASED on DATA RELEASE 25
    Draft version October 13, 2017 Typeset using LATEX twocolumn style in AASTeX61 PLANETARY CANDIDATES OBSERVED BY Kepler. VIII. A FULLY AUTOMATED CATALOG WITH MEASURED COMPLETENESS AND RELIABILITY BASED ON DATA RELEASE 25 Susan E. Thompson,1, 2, 3, ∗ Jeffrey L. Coughlin,2, 1 Kelsey Hoffman,1 Fergal Mullally,1, 2, 4 Jessie L. Christiansen,5 Christopher J. Burke,2, 1, 6 Steve Bryson,2 Natalie Batalha,2 Michael R. Haas,2, y Joseph Catanzarite,1, 2 Jason F. Rowe,7 Geert Barentsen,8 Douglas A. Caldwell,1, 2 Bruce D. Clarke,1, 2 Jon M. Jenkins,2 Jie Li,1 David W. Latham,9 Jack J. Lissauer,2 Savita Mathur,10 Robert L. Morris,1, 2 Shawn E. Seader,11 Jeffrey C. Smith,1, 2 Todd C. Klaus,2 Joseph D. Twicken,1, 2 Jeffrey E. Van Cleve,1 Bill Wohler,1, 2 Rachel Akeson,5 David R. Ciardi,5 William D. Cochran,12 Christopher E. Henze,2 Steve B. Howell,2 Daniel Huber,13, 14, 1, 15 Andrej Prša,16 Solange V. Ramírez,5 Timothy D. Morton,17 Thomas Barclay,18 Jennifer R. Campbell,2, 19 William J. Chaplin,20, 15 David Charbonneau,9 Jørgen Christensen-Dalsgaard,15 Jessie L. Dotson,2 Laurance Doyle,21, 1 Edward W. Dunham,22 Andrea K. Dupree,9 Eric B. Ford,23, 24, 25, 26 John C. Geary,9 Forrest R. Girouard,27, 2 Howard Isaacson,28 Hans Kjeldsen,15 Elisa V. Quintana,18 Darin Ragozzine,29 Avi Shporer,30 Victor Silva Aguirre,15 Jason H. Steffen,31 Martin Still,8 Peter Tenenbaum,1, 2 William F.
    [Show full text]
  • Water Worlds Cannot Composition of Planets Ranging from 2 to 4 Earth Radii (R⊕) Still Be Made Based on the Mass–Radius Relationship Alone Or the – Remains
    Growth model interpretation of planet size distribution Li Zenga,b,1, Stein B. Jacobsena, Dimitar D. Sasselovb, Michail I. Petaeva,b, Andrew Vanderburgc, Mercedes Lopez-Moralesb, Juan Perez-Mercadera, Thomas R. Mattssond, Gongjie Lie, Matthew Z. Heisingb, Aldo S. Bonomof, Mario Damassof, Travis A. Bergerg, Hao Caoa, Amit Levib, and Robin D. Wordswortha aDepartment of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138; bCenter for Astrophysics j Harvard & Smithsonian, Department of Astronomy, Harvard University, MA 02138; cDepartment of Astronomy, The University of Texas at Austin, Austin, TX 78712; dHigh Energy Density Physics Theory Department, Sandia National Laboratories, Albuquerque, NM 87185; eSchool of Physics, Georgia Institute of Technology, Atlanta, GA 30313; fIstituto Nazionale di Astrofisica–Osservatorio Astrofisico di Torino, 10025 Pino Torinese, Italy; and gInstitute for Astronomy, University of Hawaii, Honolulu, HI 96822 Edited by Neta A. Bahcall, Princeton University, Princeton, NJ, and approved March 21, 2019 (received for review July 26, 2018) The radii and orbital periods of 4,000+ confirmed/candidate exo- be distributed log-uniform, that is, flat in semimajor axis a or planets have been precisely measured by the Kepler mission. The orbital period P, beyond ∼10d(figure7ofref.12).Suchorbit radii show a bimodal distribution, with two peaks corresponding distributions of both populations challenge the photoevaporation to smaller planets (likely rocky) and larger intermediate-size plan- scenario as the cause of the gap because it strongly depends on the ets, respectively. While only the masses of the planets orbiting the orbital distance. If the gap is caused by photoevaporation, then an brightest stars can be determined by ground-based spectroscopic anticorrelation in their orbital distributions is expected (13).
    [Show full text]
  • A Spectroscopic Analysis of the California-Kepler Survey Sample: I
    Draft version March 4, 2019 Typeset using LATEX modern style in AASTeX61 A SPECTROSCOPIC ANALYSIS OF THE CALIFORNIA-KEP LER SURVEY SAMPLE: I. STELLAR PARAMETERS, PLANETARY RADII AND A SLOPE IN THE RADIUS GAP Cintia F. Martinez,1 Katia Cunha,1, 2 Luan Ghezzi,1 and Verne V. Smith3 1Observat´orioNacional, Rua General Jos´eCristino, 77, 20921-400 S~aoCrist´ov~ao,Rio de Janeiro, RJ, Brazil 2Steward Observatory, University of Arizona, 933 North Cherry Ave., Tucson, AZ 85721, USA 3National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719, USA (Received October, 2018; Revised February, 2019) Submitted to ApJ ABSTRACT We present results from a quantitative spectroscopic analysis conducted on archival Keck/HIRES high-resolution spectra from the California-Kepler Survey (CKS) sam- ple of transiting planetary host stars identified from the Kepler mission. The spectro- scopic analysis was based on a carefully selected set of Fe I and Fe II lines, resulting in precise values for the stellar parameters of effective temperature (Teff ) and surface gravity (log g). Combining the stellar parameters with Gaia DR2 parallaxes and precise distances, we derived both stellar and planetary radii for our sample, with a median internal uncertainty of 2.8% in the stellar radii and 3.7% in the planetary radii. An investigation into the distribution of planetary radii confirmed the bimodal nature of this distribution for the small radius planets found in previous studies, with peaks at: ∼1.47 ± 0.05 R⊕ and ∼2.72 ± 0.10 R⊕, with a gap at ∼ 1.9R⊕. Previous studies that modeled planetary formation that is dominated by photo-evaporation arXiv:1903.00174v1 [astro-ph.EP] 1 Mar 2019 predicted this bimodal radii distribution and the presence of a radius gap, or photo- evaporation valley.
    [Show full text]
  • 2020 Science Gap List
    ExEP Science Gap List, Rev C JPL D: 1717112 Release Date: January 1, 2020 Page 1 of 21 Approved by: Dr. Gary Blackwood Date Program Manager, Exoplanet Exploration Program Office NASA/Jet Propulsion Laboratory Dr. Douglas Hudgins Date Program Scientist Exoplanet Exploration Program Science Mission Directorate NASA Headquarters EXOPLANET EXPLORATION PROGRAM Science Gap List 2020 Karl Stapelfeldt, Program Chief Scientist Eric Mamajek, Deputy Program Chief Scientist Exoplanet Exploration Program JPL CL#20-1234 CL#20-1234 JPL Document No: 1717112 ExEP Science Gap List, Rev C JPL D: 1717112 Release Date: January 1, 2020 Page 2 of 21 Cover Art Credit: NASA/JPL-Caltech. Artist conception of the K2-138 exoplanetary system, the first multi-planet system ever discovered by citizen scientists1. K2-138 is an orangish (K1) main sequence star about 200 parsecs away, with five known planets all between the size of Earth and Neptune orbiting in a very compact architecture. The planet’s orbits form an unbroken chain of 3:2 resonances, with orbital periods ranging from 2.3 and 12.8 days, orbiting the star between 0.03 and 0.10 AU. The limb of the hot sub-Neptunian world K2-138 f looms in the foreground at the bottom, with close neighbor K2-138 e visible (center) and the innermost planet K2-138 b transiting its star. The discovery study of the K2-138 system was led by Jessie Christiansen and collaborators (2018, Astronomical Journal, Volume 155, article 57). This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
    [Show full text]
  • Giant Planets Transiting Giant Stars a DISSERTATION SUBMITTED TO
    Giant Planets Transiting Giant Stars A DISSERTATION SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAI`I AT MANOA¯ IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN ASTRONOMY August 2019 By Samuel Kai Grunblatt Dissertation Committee: Daniel Huber, Chairperson Eric J. Gaidos Andrew W. Howard Christoph J. Baranec Rolf-Peter Kudritzki Jonathan P. Williams c Copyright 2019 by Samuel K. Grunblatt All Rights Reserved ii To I. Piehler, H. Grunblatt, and H. and E. Blake iii Acknowledgements As my six years as a graduate student in Hawaii draws to a close, I'm grateful to a wide range of individuals who have made this thesis possible. Without a broad network of support and enthusiasm for my research, obtaining this degree would not have been possible. A famous scientist once said, "If I have seen further it is by standing on the shoulders of Giants." Though my achievements certainly pale in comparison, the sentiment rings true to my work. Thank you to all of you who helped me get to this point{it wouldn't have happened without you. First, I'd like to acknowledge the support of the US taxpayers. Without the funding that all of us provide, the NASA and NSF funds used to pay my salary would not be available. I'd also like to thank the citizens of the state of Hawaii. Your (retroactive) choice to allow scientific research at the summit of Maunakea was essential to the success of this research. Given the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawai`ian community, I am very grateful to have been given the opportunity to use this unique place to best further exoplanet and astronomical studies for the common good.
    [Show full text]
  • From ESPRESSO to PLATO: Detecting and Characterizing Earth-Like Planets in the Presence of Stellar Noise
    From ESPRESSO to PLATO: detecting and characterizing Earth-like planets in the presence of stellar noise Tese de Doutouramento Luisa Maria Serrano Departamento de Fisica e Astronomia do Porto, Faculdade de Ciências da Universidade do Porto Orientador: Nuno Cardoso Santos, Co-Orientadora: Susana Cristina Cabral Barros March 2020 Dedication This Ph.D. thesis is the result of 4 years of work, stress, anxiety, but, over all, fun, curiosity and desire of exploring the most hidden scientific discoveries deserved by Astrophysics. Working in Exoplanets was the beginning of the realization of a life-lasting dream, it has allowed me to enter an extremely active and productive group. For this reason my thanks go, first of all, to the ’boss’ and my Ph.D. supervisor, Nuno Santos. He allowed me to be here and introduced me in this world, a distant mirage for the master student from a university where there was no exoplanets thematic line. I also have to thank him for his humanity, not a common quality among professors. The second thank goes to Susana, who was always there for me when I had issues, not necessarily scientific ones. I finally have to thank Mahmoud; heis not listed as supervisor here, but he guided me, teaching me how to do research and giving me precious life lessons, which made me growing. There is also a long series of people I am thankful to, for rendering this years extremely interesting and sustaining me in the deepest moments. My first thought goes to my parents: they were thousands of kilometers far away from me, though they never left me alone and they listened to my complaints, joy, sadness...everything.
    [Show full text]