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Articles 1621 - 1650 of 8856

Full-Text Articles in Astrophysics and Astronomy

Addressing The Learning Loss During The Covid-19 Pandemic Through The Adaptation Of Virtual Platforms, Nazrul I. Khandaker, Anika Nawar Mayeesha, Violeta Escandon Correa, Toralv Munro, Andrew Singh, Matthew Khargie, Ality Aghedo, Jasmin Budhan, Krishna Mahabir, Belal A. Sayeed Oct 2021

Addressing The Learning Loss During The Covid-19 Pandemic Through The Adaptation Of Virtual Platforms, Nazrul I. Khandaker, Anika Nawar Mayeesha, Violeta Escandon Correa, Toralv Munro, Andrew Singh, Matthew Khargie, Ality Aghedo, Jasmin Budhan, Krishna Mahabir, Belal A. Sayeed

Publications and Research

The York College-hosted NASA MAA (MUREP AEROSPACE ACADEMY) has always played a pivotal role in minimizing the learning loss during the summer months, which was heightened during the pandemic. Support from AT&T, Con Edison and NASA enabled the MAA program at York College to offer a virtual STEM education with an earth science concentration to 1000 plus underserved K1-12 students from the community last summer, including 160 high school students. Two factors made this endeavor fruitful: allowing additional time to engage in STEM lessons and increasing self-motivation to successfully accomplish assigned tasks. Students built partnerships and resolved technical issues with …


Leveraging The Popularity Of Virtual Conferencing Due To The Covid-19 Pandemic To Create New Opportunities For Stem Education, Andrew Singh, Nazrul I. Khandaker, Violeta Escandon Correa, Omadevi Singh, Ariel Skobelsky, Farhan Tanvir, Brian Sukhnandan, Matthew Khargie, Elton Selby, Masud Ahmed Oct 2021

Leveraging The Popularity Of Virtual Conferencing Due To The Covid-19 Pandemic To Create New Opportunities For Stem Education, Andrew Singh, Nazrul I. Khandaker, Violeta Escandon Correa, Omadevi Singh, Ariel Skobelsky, Farhan Tanvir, Brian Sukhnandan, Matthew Khargie, Elton Selby, Masud Ahmed

Publications and Research

Due to the COVID-19 pandemic, virtual learning has become a necessity for K9-16 education. Virtual classwork has been administered through platforms such as Google Classroom, Clever, and iReady. During the summer of 2021, the City University of New York (C.U.N.Y) York College campus hosted its NASA MAA MUREP (Minority University Research and Education Project Aerospace Academy) program virtually using a combination of Zoom, Google Docs, and even Canva, which some students requested as a more intuitive alternative to Microsoft PowerPoint. Students were mentored to use the scientific method to explore their interests in the STEM field, with a geoscience or …


Multi-Faceted Geoscience Research Using Open Access Resources: The Successful Participation Of K9-16 Students, Nazrul I. Khandaker, Noshin Sharmili, Omadevi Singh, Gurwinder Sahota, Sol De Leon, Matthew Khargie, Ali Zarine, Krishna Mahabir, Adacia Teemal, Mildred M. Selby Oct 2021

Multi-Faceted Geoscience Research Using Open Access Resources: The Successful Participation Of K9-16 Students, Nazrul I. Khandaker, Noshin Sharmili, Omadevi Singh, Gurwinder Sahota, Sol De Leon, Matthew Khargie, Ali Zarine, Krishna Mahabir, Adacia Teemal, Mildred M. Selby

Publications and Research

Students interested in geosciences, for the most part, missed out their traditional field- based research activities due to strict social distancing, travel restrictions and/or lacking financial support. An absence of physical laboratory opportunities forced students to choose topics deemed doable through online research. Available data from online sources on extreme weather related case studies, flooding, droughts, groundwater depletion in urban and suburban areas, coastal erosion rate, sealevel rise, landslides, earthquakes, volcanic eruptions, and atmospheric pollution became quite handy and lucrative. Readily available pertinent data sources enabled K9-16 students to conduct summer research at “stay home” situations. Selective peer mentoring was …


All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars In The Early O3 Ligo Data, R. Abbott, T. D. Abbott, S. Abraham, Teviet Creighton, Mario C. Diaz, Volker Quetschke, Karla E. Ramirez, Wen Hui Wang Oct 2021

All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars In The Early O3 Ligo Data, R. Abbott, T. D. Abbott, S. Abraham, Teviet Creighton, Mario C. Diaz, Volker Quetschke, Karla E. Ramirez, Wen Hui Wang

Physics & Astronomy Faculty Publications

We report on an all-sky search for continuous gravitational waves in the frequency band 20–2000 Hz and with a frequency time derivative in the range of [−1.0,+0.1]×10−8  Hz/s. Such a signal could be produced by a nearby, spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the LIGO data from the first six months of Advanced LIGO’s and Advanced Virgo’s third observational run, O3. No periodic gravitational wave signals are observed, and 95% confidence-level (C.L.) frequentist upper limits are placed on their strengths. The lowest upper limits on worst-case (linearly polarized) strain amplitude h0 are ∼1.7×10−25 …


All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars In The Early O3 Ligo Data, Ligo Scientific Collaboration, Virgo Collaboration, Kagra Collaboration, Tiffany Z. Summerscales Oct 2021

All-Sky Search For Continuous Gravitational Waves From Isolated Neutron Stars In The Early O3 Ligo Data, Ligo Scientific Collaboration, Virgo Collaboration, Kagra Collaboration, Tiffany Z. Summerscales

Faculty Publications

We report on an all-sky search for continuous gravitational waves in the frequency band 20–2000 Hz and with a frequency time derivative in the range of [−1.0,+0.1]×10−8  Hz/s. Such a signal could be produced by a nearby, spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the LIGO data from the first six months of Advanced LIGO’s and Advanced Virgo’s third observational run, O3. No periodic gravitational wave signals are observed, and 95% confidence-level (C.L.) frequentist upper limits are placed on their strengths. The lowest upper limits on worst-case (linearly polarized) strain amplitude h0 are ∼1.7×10−25 …


Initial Acoustoelastic Measurements In Olivine: Investigating The Effect Of Stress On P- And S-Wave Velocities, Taryn K. Traylor, Pamela C. Burnley, M. L. Whitaker Oct 2021

Initial Acoustoelastic Measurements In Olivine: Investigating The Effect Of Stress On P- And S-Wave Velocities, Taryn K. Traylor, Pamela C. Burnley, M. L. Whitaker

Geoscience Faculty Research

It is well known that elasticity is a key physical property in the determination of the structure and composition of the Earth and provides critical information for the interpretation of seismic data. This study investigates the stress-induced variation in elastic wave velocities, known as the acoustoelastic effect, in San Carlos olivine. A recently developed experimental ultrasonic acoustic system, the Directly Integrated Acoustic System Combined with Pressure Experiments (DIASCoPE), was used with the D-DIA multi-anvil apparatus to transmit ultrasonic sound waves and collect the reflections. We use the DIASCoPE to obtain longitudinal (P) and shear (S) elastic wave velocities from San …


Galaxy And Mass Assembly (Gama): The Environmental Impact On Sfr And Metallicity In Galaxy Groups, D Sotillo-Ramos, M A. Lara-López, A M. Pérez-García, R Pérez-Martínez, A M. Hopkins, Benne Holwerda, J Liske, A R. López-Sánchez, M S. Owers, K A. Pimbblet Oct 2021

Galaxy And Mass Assembly (Gama): The Environmental Impact On Sfr And Metallicity In Galaxy Groups, D Sotillo-Ramos, M A. Lara-López, A M. Pérez-García, R Pérez-Martínez, A M. Hopkins, Benne Holwerda, J Liske, A R. López-Sánchez, M S. Owers, K A. Pimbblet

Faculty and Staff Scholarship

We present a study of the relationships and environmental dependencies between stellar mass, star formation rate, and gas metallicity for more than 700 galaxies in groups up to redshift 0.35 from the Galaxy And Mass Assembly (GAMA) survey. To identify the main drivers, our sample was analysed as a function of group-centric distance, projected galaxy number density, and stellar mass. By using control samples of more than 16 000 star-forming field galaxies and volume-limited samples, we find that the highest enhancement in SFR (0.3 dex) occurs in galaxies with the lowest local density. In contrast to previous work, our data …


Search For Lepton-Flavor-Violating Tau-Lepton Decays To ℓγ At Belle, K. Uno, K. Hayasaka, K. Inami, I. Adachi, H. Aihara, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, J. Bennett, F. Bernlochner, M. Bessner, V. Bhardwaj, J. Biswal, A. Bobrov, G. Bonvicini, A. Bozek, M. Bračko Oct 2021

Search For Lepton-Flavor-Violating Tau-Lepton Decays To ℓγ At Belle, K. Uno, K. Hayasaka, K. Inami, I. Adachi, H. Aihara, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, J. Bennett, F. Bernlochner, M. Bessner, V. Bhardwaj, J. Biswal, A. Bobrov, G. Bonvicini, A. Bozek, M. Bračko

Faculty and Student Publications

Charged lepton flavor violation is forbidden in the Standard Model but possible in several new physics scenarios. In many of these models, the radiative decays τ± → ℓ±γ (ℓ = e, μ) are predicted to have a sizeable probability, making them particularly interesting channels to search at various experiments. An updated search via τ± → ℓ±γ using full data of the Belle experiment, corresponding to an integrated luminosity of 988 fb−1, is reported for charged lepton flavor violation. No significant excess over background predictions from the Standard Model is observed, and the upper limits on the branching fractions, B(τ± → …


Flavor Su(3) In Cabibbo-Favored D-Meson Decays, Bhubanjyoti Bhattacharya, Alakabha Datta, Alexey A. Petrov, John Waite Oct 2021

Flavor Su(3) In Cabibbo-Favored D-Meson Decays, Bhubanjyoti Bhattacharya, Alakabha Datta, Alexey A. Petrov, John Waite

Faculty and Student Publications

Model-independent description of nonleptonic decays of charmed mesons is a challenging task due to large nonperturbative effects of strong interactions on the transition amplitudes. We discuss the equivalence of two different flavor-SU(3)-based descriptions of Cabibbo-favored non-leptonic decays of charmed mesons to two-pseudoscalars final states including the η and η′ mesons.


Hd 183579b: A Warm Sub-Neptune Transiting A Solar Twin Detected By Tess, T. Gan, M. Bedell, S. X. Wang, D. Foreman-Mackey, J. Meléndez, S. Mao, K. G. Stassun, S. B. Howell, C. Ziegler, R. A. Wittenmyer, C. Hellier, K. A. Collins, A. Shporer, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, B. C. Addison, S. Ballard, T. Barclay, J. L. Bean, B. P. Bowler, C. Briceño, I. J. M. Crossfield, J. Dittman, J. Horner, Eric L.N. Jensen, S. R. Kane, J. Kielkopf, L. Kreidberg, N. Law, A. W. Mann, M. W. Mengel, E. D. Morgan, J. Okumura, H. P. Osborn, M. Paegert, P. Plavchan, R. P. Schwarz, B. Shiao, J. C. Smith, L. Spina, C. G. Tinney, G. Torres, J. D. Twicken, M. Vezie, G. Wang, D. J. Wright, H. Zhang Oct 2021

Hd 183579b: A Warm Sub-Neptune Transiting A Solar Twin Detected By Tess, T. Gan, M. Bedell, S. X. Wang, D. Foreman-Mackey, J. Meléndez, S. Mao, K. G. Stassun, S. B. Howell, C. Ziegler, R. A. Wittenmyer, C. Hellier, K. A. Collins, A. Shporer, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, B. C. Addison, S. Ballard, T. Barclay, J. L. Bean, B. P. Bowler, C. Briceño, I. J. M. Crossfield, J. Dittman, J. Horner, Eric L.N. Jensen, S. R. Kane, J. Kielkopf, L. Kreidberg, N. Law, A. W. Mann, M. W. Mengel, E. D. Morgan, J. Okumura, H. P. Osborn, M. Paegert, P. Plavchan, R. P. Schwarz, B. Shiao, J. C. Smith, L. Spina, C. G. Tinney, G. Torres, J. D. Twicken, M. Vezie, G. Wang, D. J. Wright, H. Zhang

Physics & Astronomy Faculty Works

We report the discovery and characterization of a transiting warm sub-Neptune planet around the nearby bright (V = 8.75 mag, K = 7.15 mag) solar twin HD 183579, delivered by the Transiting Exoplanet Survey Satellite (TESS). The host star is located 56.8 ± 0.1 pc away with a radius of R* = 0.97 ± 0.02 R⊙ and a mass of M* = 1.03 ± 0.05 M⊙. We confirm the planetary nature by combining space and ground-based photometry, spectroscopy, and imaging. We find that HD 183579b (TOI-1055b) has a radius of Rp …


Toi-3362b: A Proto Hot Jupiter Undergoing High-Eccentricity Tidal Migration, J. Dong, C. X. Huang, G. Zhou, R. I. Dawson, J. E. Rodriguez, J. D. Eastman, K. A. Collins, S. N. Quinn, A. Shporer, A. H. M. J. Triaud, S. Wang, T. Beatty, J. M. Jackson, K. I. Collins, L. Abe, O. Suarez, N. Crouzet, D. Mékarnia, G. Dransfield, Eric L.N. Jensen, C. Stockdale, K. Barkaoui, A. Heitzmann, D. J. Wright, B. C. Addison, R. A. Wittenmyer, J. Okumura, B. P. Bowler, J. Horner, S. R. Kane, J. Kielkopf, H. Liu, P. Plavchan, M. W. Mengel, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, J. L. Christiansen, M. Paegert Oct 2021

Toi-3362b: A Proto Hot Jupiter Undergoing High-Eccentricity Tidal Migration, J. Dong, C. X. Huang, G. Zhou, R. I. Dawson, J. E. Rodriguez, J. D. Eastman, K. A. Collins, S. N. Quinn, A. Shporer, A. H. M. J. Triaud, S. Wang, T. Beatty, J. M. Jackson, K. I. Collins, L. Abe, O. Suarez, N. Crouzet, D. Mékarnia, G. Dransfield, Eric L.N. Jensen, C. Stockdale, K. Barkaoui, A. Heitzmann, D. J. Wright, B. C. Addison, R. A. Wittenmyer, J. Okumura, B. P. Bowler, J. Horner, S. R. Kane, J. Kielkopf, H. Liu, P. Plavchan, M. W. Mengel, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, J. L. Christiansen, M. Paegert

Physics & Astronomy Faculty Works

High-eccentricity tidal migration is a possible way for giant planets to be placed in short-period orbits. If this happens often, one would expect to catch proto hot Jupiters on highly elliptical orbits undergoing high-eccentricity tidal migration. As of yet, few such systems have been discovered. Here, we introduce TOI-3362b (TIC-464300749b), an 18.1 day, 5 MJup planet orbiting a main-sequence F-type star that is likely undergoing high-eccentricity tidal migration. The orbital eccentricity is 0.815 (+0.023)/(-0.032). With a semimajor axis of 0.153 (+0.002)/(-0.003) au, the planet's orbit is expected to shrink to a final orbital radius of 0.051 (+0.008)/(-0.006) au after …


Toi-431/Hip 26013: A Super-Earth And A Sub-Neptune Transiting A Bright, Early K Dwarf, With A Third Rv Planet, A. Osborn, D. J. Armstrong, B. Cale, R. Brahm, R. A. Wittenmyer, F. Dai, I. J. M. Crossfield, E. M. Bryant, V. Adibekyan, R. Cloutier, K. A. Collins, E. Delgado Mena, M. Fridlund, C. Hellier, S. B. Howell, G. W. King, J. Lillo-Box, J. Otegi, S. Sousa, K. G. Stassun, E. C. Matthews, C. Ziegler, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, J. S. Acton, B. C. Addison, D. R. Anderson, S. Ballard, D. Barrado, S. C. C. Barros, N. Batalha, D. Bayliss, T. Barclay, B. Benneke, J. Berberian Jr., F. Bouchy, B. P. Bowler, C. Briceño, C. J. Burke, M. R. Burleigh, S. L. Casewell, D. Ciardi, K. I. Collins, B. F. Cooke, O. D. S. Demangeon, R. F. Díaz, C. Dorn, D. Dragomir, C. Dressing, X. Dumusque, N. Espinoza, P. Figueira, B. Fulton, E. Furlan, E. Gaidos, C. Geneser, S. Gill, M. R. Road, E. J. Gonzales, V. Gorjian, M. N. Günther, R. Helled, B. A. Henderson, T. Henning, A. Hogan, S. Hojjatpanah, J. Horner, A. W. Howard, S. Hoyer, D. Huber, H. Isaacson, J. S. Jenkins, Eric L.N. Jensen, A. Jordán, A. R. Kane, R. C. Kidwell Jr., J. Kielkopf, N. Law, M. Lendl, M. Lund, R. A. Matson, A. W. Mann, J. Mccormac, M. W. Mengel, F. Y. Morales, L. D. Nielsen, J. Okumura, H. P. Osborn, E. A. Petigura, P. Plavchan, D. Pollacco, E. V. Quintana, L. Raynard, P. Robertson, M. E. Rose, A. Roy, M. Reefe, A. Santerne, N. C. Santos, P. Sarkis, J. Schlieder, R. P. Schwarz, N. J. Scott, A. Shporer, A. M. S. Smith, C. Stibbard, C. Stockdale, P. A. Strøm, J. D. Twicken, T.-G. Tan, A. Tanner, J. Teske, R. H. Tilbrook, C. G. Tinney, S. Udry, J. N. Villaseñor, J. I. Vines, S. X. Wang, L. M. Weiss, R. G. West, P. J. Wheatley, D. J. Wright, H. Zhang, F. Zohrabi Oct 2021

Toi-431/Hip 26013: A Super-Earth And A Sub-Neptune Transiting A Bright, Early K Dwarf, With A Third Rv Planet, A. Osborn, D. J. Armstrong, B. Cale, R. Brahm, R. A. Wittenmyer, F. Dai, I. J. M. Crossfield, E. M. Bryant, V. Adibekyan, R. Cloutier, K. A. Collins, E. Delgado Mena, M. Fridlund, C. Hellier, S. B. Howell, G. W. King, J. Lillo-Box, J. Otegi, S. Sousa, K. G. Stassun, E. C. Matthews, C. Ziegler, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, J. S. Acton, B. C. Addison, D. R. Anderson, S. Ballard, D. Barrado, S. C. C. Barros, N. Batalha, D. Bayliss, T. Barclay, B. Benneke, J. Berberian Jr., F. Bouchy, B. P. Bowler, C. Briceño, C. J. Burke, M. R. Burleigh, S. L. Casewell, D. Ciardi, K. I. Collins, B. F. Cooke, O. D. S. Demangeon, R. F. Díaz, C. Dorn, D. Dragomir, C. Dressing, X. Dumusque, N. Espinoza, P. Figueira, B. Fulton, E. Furlan, E. Gaidos, C. Geneser, S. Gill, M. R. Road, E. J. Gonzales, V. Gorjian, M. N. Günther, R. Helled, B. A. Henderson, T. Henning, A. Hogan, S. Hojjatpanah, J. Horner, A. W. Howard, S. Hoyer, D. Huber, H. Isaacson, J. S. Jenkins, Eric L.N. Jensen, A. Jordán, A. R. Kane, R. C. Kidwell Jr., J. Kielkopf, N. Law, M. Lendl, M. Lund, R. A. Matson, A. W. Mann, J. Mccormac, M. W. Mengel, F. Y. Morales, L. D. Nielsen, J. Okumura, H. P. Osborn, E. A. Petigura, P. Plavchan, D. Pollacco, E. V. Quintana, L. Raynard, P. Robertson, M. E. Rose, A. Roy, M. Reefe, A. Santerne, N. C. Santos, P. Sarkis, J. Schlieder, R. P. Schwarz, N. J. Scott, A. Shporer, A. M. S. Smith, C. Stibbard, C. Stockdale, P. A. Strøm, J. D. Twicken, T.-G. Tan, A. Tanner, J. Teske, R. H. Tilbrook, C. G. Tinney, S. Udry, J. N. Villaseñor, J. I. Vines, S. X. Wang, L. M. Weiss, R. G. West, P. J. Wheatley, D. J. Wright, H. Zhang, F. Zohrabi

Physics & Astronomy Faculty Works

We present the bright (Vmag = 9.12), multiplanet system TOI-431, characterized with photometry and radial velocities (RVs). We estimate the stellar rotation period to be 30.5 ± 0.7 d using archival photometry and RVs. Transiting Exoplanet Survey Satellite (TESS) objects of Interest (TOI)-431 b is a super-Earth with a period of 0.49 d, a radius of 1.28 ± 0.04 R⊕, a mass of 3.07 ± 0.35 M⊕, and a density of 8.0 ± 1.0 g cm⁻³; TOI-431 d is a sub-Neptune with a period of 12.46 d, a radius of 3.29 ± 0.09 …


Two Bright M Dwarfs Hosting Ultra-Short-Period Super-Earths With Earth-Like Compositions, T. Hirano, J. H. Livingston, A. Fukui, N. Narita, H. Harakawa, H. T. Ishikawa, K. Miyakawa, T. Kimura, A. Nakayama, N. Fujita, Y. Hori, K. G. Stassun, A. Bieryla, C. Cadieux, D. R. Ciardi, K. A. Collins, M. Ikoma, A. Vanderburg, T. Barclay, C. E. Brasseur, J. P. De Leon, J. P. Doty, R. Doyon, E. Esparza-Borges, G. A. Esquerdo, E. Furlan, E. Gaidos, E. J. Gonzales, K. Hodapp, S. B. Howell, K. Isogai, S. Jacobson, J. M. Jenkins, Eric L.N. Jensen, K. Kawauchi, T. Kotani, T. Kudo, S. Kurita, T. Kurokawa, N. Kusakabe, M. Kuzuhara, D. Lafrenière, D. W. Latham, B. Massey, M. Mori, F. Murgas, J. Nishikawa, T. Nishiumi, M. Omiya, M. Paegert, E. Palle, H. Parviainen, S. N. Quinn, G. R. Ricker, R. P. Schwarz, S. Seager, M. Tamura, P. Tenenbaum, Y. Terada, R. K. Vanderspek, S. Vievard, N. Watanabe, J. N. Winn Oct 2021

Two Bright M Dwarfs Hosting Ultra-Short-Period Super-Earths With Earth-Like Compositions, T. Hirano, J. H. Livingston, A. Fukui, N. Narita, H. Harakawa, H. T. Ishikawa, K. Miyakawa, T. Kimura, A. Nakayama, N. Fujita, Y. Hori, K. G. Stassun, A. Bieryla, C. Cadieux, D. R. Ciardi, K. A. Collins, M. Ikoma, A. Vanderburg, T. Barclay, C. E. Brasseur, J. P. De Leon, J. P. Doty, R. Doyon, E. Esparza-Borges, G. A. Esquerdo, E. Furlan, E. Gaidos, E. J. Gonzales, K. Hodapp, S. B. Howell, K. Isogai, S. Jacobson, J. M. Jenkins, Eric L.N. Jensen, K. Kawauchi, T. Kotani, T. Kudo, S. Kurita, T. Kurokawa, N. Kusakabe, M. Kuzuhara, D. Lafrenière, D. W. Latham, B. Massey, M. Mori, F. Murgas, J. Nishikawa, T. Nishiumi, M. Omiya, M. Paegert, E. Palle, H. Parviainen, S. N. Quinn, G. R. Ricker, R. P. Schwarz, S. Seager, M. Tamura, P. Tenenbaum, Y. Terada, R. K. Vanderspek, S. Vievard, N. Watanabe, J. N. Winn

Physics & Astronomy Faculty Works

We present observations of two bright M dwarfs (TOI-1634 and TOI-1685: J = 9.5–9.6) hosting ultra-short-period (USP) planets identified by the TESS mission. The two stars are similar in temperature, mass, and radius (Teff ≈ 3500 K, M⋆ ≈ 0.45–0.46 M⊙, and R⋆ ≈ 0.45–0.46 R⊙), and the planets are both super-Earth size (1.25 R⊕ < Rp < 2.0 R⊕). For both systems, light curves from ground-based photometry exhibit planetary transits, whose depths are consistent with those from the TESS photometry. We also refine the transit ephemerides based on the ground-based …


The Magellan-Tess Survey. I. Survey Description And Midsurvey Results, J. Teske, S. X. Wang, A. Wolfgang, T. Gan, M. Plotnykov, D. J. Armstrong, R. P. Butler, B. Cale, J. D. Crane, W. Howard, Eric L.N. Jensen, N. Law, S. A. Shectman, P. Plavchan, D. Valencia, A. Vanderburg, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, V. Adibekyan, D. Barrado, S. C. C. Barros, Z. Benkhaldoun, D. J. A. Brown, E. M. Bryant, J. Burt, D. A. Caldwell, D. Charbonneau, R. Cloutier, K. A. Collins, K. I. Collins, K. D. Colon, D. M. Conti, O. D. S. Demangeon, J. D. Eastman, M. Elmufti, F. Feng, E. Flowers, N. M. Guerrero, S. Hojjatpanah, J. M. Irwin, G. Isopi, J. Lillo-Box, F. Mallia, B. Massey, M. Mori, S. E. Mullally, N. Narita, T. Nishiumi, A. Osborn, M. Paegert, J. P. De Leon, S. N. Quinn, M. Reefe, R. P. Schwarz, A. Shporer, A. Soubkiou, S. G. Sousa, C. Stockdale, P. A. Strøm, T.-G. Tan, J. Tang, P. Tenenbaum, P. J. Wheatley, J. Wittrock, D. A. Yahalomi, F. Zohrabi Oct 2021

The Magellan-Tess Survey. I. Survey Description And Midsurvey Results, J. Teske, S. X. Wang, A. Wolfgang, T. Gan, M. Plotnykov, D. J. Armstrong, R. P. Butler, B. Cale, J. D. Crane, W. Howard, Eric L.N. Jensen, N. Law, S. A. Shectman, P. Plavchan, D. Valencia, A. Vanderburg, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, V. Adibekyan, D. Barrado, S. C. C. Barros, Z. Benkhaldoun, D. J. A. Brown, E. M. Bryant, J. Burt, D. A. Caldwell, D. Charbonneau, R. Cloutier, K. A. Collins, K. I. Collins, K. D. Colon, D. M. Conti, O. D. S. Demangeon, J. D. Eastman, M. Elmufti, F. Feng, E. Flowers, N. M. Guerrero, S. Hojjatpanah, J. M. Irwin, G. Isopi, J. Lillo-Box, F. Mallia, B. Massey, M. Mori, S. E. Mullally, N. Narita, T. Nishiumi, A. Osborn, M. Paegert, J. P. De Leon, S. N. Quinn, M. Reefe, R. P. Schwarz, A. Shporer, A. Soubkiou, S. G. Sousa, C. Stockdale, P. A. Strøm, T.-G. Tan, J. Tang, P. Tenenbaum, P. J. Wheatley, J. Wittrock, D. A. Yahalomi, F. Zohrabi

Physics & Astronomy Faculty Works

Kepler revealed that roughly one-third of Sunlike stars host planets orbiting within 100 days and between the size of Earth and Neptune. How do these planets form, what are they made of, and do they represent a continuous population or multiple populations? To help address these questions, we began the Magellan-TESS Survey (MTS), which uses Magellan II/PFS to obtain radial velocity (RV) masses of 30 TESS-detected exoplanets and develops an analysis framework that connects observed planet distributions to underlying populations. In the past, small-planet RV measurements have been challenging to obtain due to host star faintness and low RV semiamplitudes …


The Mass Of Β Pictoris C From Β Pictoris B Orbital Motion, S. Lacour, J. J. Wang, L. Rodet, M. Nowak, J. Shangguan, H. Beust, A. M. Lagrange, R. Abuter, A. Amorim, R. Asensio-Torres, M. Benisty, J. P. Berger, S. Blunt, A. Boccaletti, A. Bohn, M. L. Bolzer, M. Bonnefoy, H. Bonnet, G. Bourdarot, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, G. Chauvin, E. Choquet, V. Christiaens, Y. Clénet, V. Coudé Du Foresto, A. Cridland, R. Dembet, J. Dexter, P. T. De Zeeuw, K. Ward-Duong, Et Al Oct 2021

The Mass Of Β Pictoris C From Β Pictoris B Orbital Motion, S. Lacour, J. J. Wang, L. Rodet, M. Nowak, J. Shangguan, H. Beust, A. M. Lagrange, R. Abuter, A. Amorim, R. Asensio-Torres, M. Benisty, J. P. Berger, S. Blunt, A. Boccaletti, A. Bohn, M. L. Bolzer, M. Bonnefoy, H. Bonnet, G. Bourdarot, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, G. Chauvin, E. Choquet, V. Christiaens, Y. Clénet, V. Coudé Du Foresto, A. Cridland, R. Dembet, J. Dexter, P. T. De Zeeuw, K. Ward-Duong, Et Al

Astronomy: Faculty Publications

Aims. We aim to demonstrate that the presence and mass of an exoplanet can now be effectively derived from the astrometry of another exoplanet. Methods. We combined previous astrometry of β Pictoris b with a new set of observations from the GRAVITY interferometer. The orbital motion of β Pictoris b is fit using Markov chain Monte Carlo simulations in Jacobi coordinates. The inner planet, β Pictoris c, was also reobserved at a separation of 96 mas, confirming the previous orbital estimations. Results. From the astrometry of planet b only, we can (i) detect the presence of β Pictoris c and …


The Morphology And Evolution Of Transverse Aeolian Ridges On Mars, Timothy Paul Nagle-Mcnaughton Oct 2021

The Morphology And Evolution Of Transverse Aeolian Ridges On Mars, Timothy Paul Nagle-Mcnaughton

Earth and Planetary Sciences ETDs

Transverse aeolian ridges (TARs) are enigmatic and largely relict bedforms on the surface of Mars. TARs are sparsely distributed but common on Mars, but their history, preservation, and past role in the sediment cycle is not well understood. First described in 2003, and detailed extensively in 2008, our study of TARs has been narrowly focused in the last decade, with more and more research noting their presence, but little investigation of the features themselves. Recent work has mostly focused on identifying Terran analogues for TARs, but TARs remain largely a unique Martian feature. In this manuscript, I clarify and refine …


Realistic Binary Neutron Stars Collisions Simulations: Challenges And Opportunities, Maria Babiuc-Hamilton Oct 2021

Realistic Binary Neutron Stars Collisions Simulations: Challenges And Opportunities, Maria Babiuc-Hamilton

Physics Faculty Research

Since 2015, when the LIGO-Virgo collaboration announced the first simultaneous detections of gravitational waves (GW150914) until now, more than 66 gravitational wave detections were reported, but only two signals came from a binary neutron star collision, the GW170817 and GW190425 events. GW170817 was accompanied by an electromagnetic outburst manifested as a kilonova and an off-axis jet. However, no conclusive electromagnetic signature was found to come from the GW190425. Indeed, nature proves again more complicated than our models, and it is still a big question how to model kilonovae, or to understand the mechanisms driving astrophysical jets and gamma ray bursts. …


Deep Underground Neutrino Experiment (Dune) Near Detector Conceptual Design Report, A. Abed Abud, B. Abi, R. Acciarri, M. A. Acero, G. Adamov, D. Adams, M. Adinolfi, A. Aduzskiewicz, Z. Ahmad, J. Ahmed, T. Alion, S. Alonso Monsalve, M. Alrashed, C. Alt, A. Alton, P. Amedo, J. Anderson, C. Andreopoulos, M. P. Andrews, F. Andrianala, Roberto Petti, Et. Al. Sep 2021

Deep Underground Neutrino Experiment (Dune) Near Detector Conceptual Design Report, A. Abed Abud, B. Abi, R. Acciarri, M. A. Acero, G. Adamov, D. Adams, M. Adinolfi, A. Aduzskiewicz, Z. Ahmad, J. Ahmed, T. Alion, S. Alonso Monsalve, M. Alrashed, C. Alt, A. Alton, P. Amedo, J. Anderson, C. Andreopoulos, M. P. Andrews, F. Andrianala, Roberto Petti, Et. Al.

Faculty Publications

The Deep Underground Neutrino Experiment (DUNE) is an international, world-class experiment aimed at exploring fundamental questions about the universe that are at the forefront of astrophysics and particle physics research. DUNE will study questions pertaining to the preponderance of matter over antimatter in the early universe, the dynamics of supernovae, the subtleties of neutrino interaction physics, and a number of beyond the Standard Model topics accessible in a powerful neutrino beam. A critical component of the DUNE physics program involves the study of changes in a powerful beam of neutrinos, i.e., neutrino oscillations, as the neutrinos propagate a long distance. …


The Loneliest Galaxies In The Universe: A Gama And Galaxyzoo Study On Void Galaxy Morphology, Lori E. Porter, Benne W. Holwerda Sep 2021

The Loneliest Galaxies In The Universe: A Gama And Galaxyzoo Study On Void Galaxy Morphology, Lori E. Porter, Benne W. Holwerda

The Cardinal Edge

The large-scale structure (LSS) of the universe is comprised of galaxy filaments, tendrils, and voids. The majority of the universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside voids are void galaxies and expected to be some of the most isolated objects in the universe. However, their standard morphology remains poorly studied. This study, using the Galaxy and Mass Assembly (GAMA) survey and Galaxy Zoo’s SDSS survey, aims to remedy this. To do so, survey results from GAMA have been plotted using the Sérsic index (n) to analyze morphology, …


Following The Lithium: Tracing Li-Bearing Molecules Across Age, Mass, And Gravity In Brown Dwarfs, Ehsan Gharib-Nezhad, Mark S. Marley, Natasha E. Batalha, Channon Visscher, Richard S. Freedman, Roxana E. Lupu Sep 2021

Following The Lithium: Tracing Li-Bearing Molecules Across Age, Mass, And Gravity In Brown Dwarfs, Ehsan Gharib-Nezhad, Mark S. Marley, Natasha E. Batalha, Channon Visscher, Richard S. Freedman, Roxana E. Lupu

Faculty Work Comprehensive List

Lithium is an important element for the understanding of ultracool dwarfs because it is lost to fusion at masses above ∼68 MJ. Hence, the presence of atomic Li has served as an indicator of the nearby H-burning boundary at about 75 MJ between brown dwarfs and very low mass stars. Historically, the “lithium test,” a search for the presence of the Li line at 670.8 nm, has been a marker if an object has a substellar mass. While the Li test could, in principle, be used to distinguish masses of later-type L–T dwarfs, Li is predominantly no longer found as …


Measurements Of The Branching Fractions Of The Semileptonic Decays Ξc0 → Ξ-ℓ+Νℓ And The Asymmetry Parameter Of Ξc0 → Ξ-Π+, Y. B. Li, C. P. Shen, I. Adachi, K. Adamczyk, H. Aihara, S. Al Said, D. M. Asner, T. Aushev, R. Ayad, V. Babu, P. Behera, J. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka, J. Biswal, G. Bonvicini, A. Bozek Sep 2021

Measurements Of The Branching Fractions Of The Semileptonic Decays Ξc0 → Ξ-ℓ+Νℓ And The Asymmetry Parameter Of Ξc0 → Ξ-Π+, Y. B. Li, C. P. Shen, I. Adachi, K. Adamczyk, H. Aihara, S. Al Said, D. M. Asner, T. Aushev, R. Ayad, V. Babu, P. Behera, J. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka, J. Biswal, G. Bonvicini, A. Bozek

Faculty and Student Publications

Using data samples of 89.5 and 711 fb-1 recorded at energies of s=10.52 and 10.58 GeV, respectively, with the Belle detector at the KEKB e+e- collider, we report measurements of branching fractions of semileptonic decays Ξc0→Ξ-ℓ+νℓ (ℓ=e or μ) and the CP-asymmetry parameter of Ξc0→Ξ-π+ decay. The branching fractions are measured to be B(Ξc0→Ξ-e+νe)=(1.31±0.04±0.07±0.38)% and B(Ξc0→Ξ-μ+νμ)=(1.27±0.06±0.10±0.37)%, and the decay parameter αΞπ is measured to be 0.63±0.03±0.01 with much improved precision compared with the current world average. The corresponding ratio B(Ξc0→Ξ-e+νe)/B(Ξc0→Ξ-μ+νμ) is 1.03±0.05±0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter ACP=(αΞ-π++αΞ¯+π-)/(αΞ-π+-αΞ¯+π-)=0.024±0.052±0.014 is found …


Gw Ori: Circumtriple Rings And Planets, Jeremy L. Smallwood, Rebecca Nealon, Cheng Chen, Rebecca G. Martin, Jiaqing Bi, Ruobing Dong, Christophe Pinte Sep 2021

Gw Ori: Circumtriple Rings And Planets, Jeremy L. Smallwood, Rebecca Nealon, Cheng Chen, Rebecca G. Martin, Jiaqing Bi, Ruobing Dong, Christophe Pinte

Physics & Astronomy Faculty Research

GW Ori is a hierarchical triple star system with a misaligned circumtriple protoplanetary disc. Recent Atacama Large Millimeter/submillimeter Array observations have identified three dust rings with a prominent gap at 100 au and misalignments between each of the rings. A break in the gas disc may be driven by the torque from either the triple star system or a planet that is massive enough to carve a gap in the disc. Once the disc is broken, the rings nodally precess on different time-scales and become misaligned. We investigate the origins of the dust rings by means of N-body integrations and …


Inelastic, Exchange, And Reactive Processes In Rovibrationally Excited Collisions Of Hd With H, Boyi Zhou, Benhui Yang, Balakrishnan Naduvalath, B. K. Kendrick, Maodu Chen, P. C. Stancil Sep 2021

Inelastic, Exchange, And Reactive Processes In Rovibrationally Excited Collisions Of Hd With H, Boyi Zhou, Benhui Yang, Balakrishnan Naduvalath, B. K. Kendrick, Maodu Chen, P. C. Stancil

Chemistry and Biochemistry Faculty Research

The HD molecule is an important coolant in early universe chemistry models and a tracer of H2 in star-forming regions. Rate coefficients for collisional excitation and de-excitation of HD rotational and vibrational levels form important ingredients in astrophysical models. While collisions with He, H2, and H are the most important, available data for H + HD collisions are largely limited to temperatures less than 1000 K for the vibrational ground state, low-lying rotational levels of the v = 1 HD vibrational level, or computed without reactive contributions. Here, through explicit quantum scattering calculations, we report extensive data for rovibrational transitions …


Ligo’S Quantum Response To Squeezed States, L. Mcculler, S. E. Dwyer, A. C. Green, Haocun Yu, K. Kuns, L. Barsotti, C. D. Blair, D. D. Brown, A. Effler, Karla E. Ramirez Sep 2021

Ligo’S Quantum Response To Squeezed States, L. Mcculler, S. E. Dwyer, A. C. Green, Haocun Yu, K. Kuns, L. Barsotti, C. D. Blair, D. D. Brown, A. Effler, Karla E. Ramirez

Physics & Astronomy Faculty Publications

Gravitational wave interferometers achieve their profound sensitivity by combining a Michelson interferometer with optical cavities, suspended masses, and now, squeezed quantum states of light. These states modify the measurement process of the LIGO, VIRGO and GEO600 interferometers to reduce the quantum noise that masks astrophysical signals; thus, improvements to squeezing are essential to further expand our gravitational view of the Universe. Further reducing quantum noise will require both lowering decoherence from losses as well more sophisticated manipulations to counter the quantum back-action from radiation pressure. Both tasks require fully understanding the physical interactions between squeezed light and the many components …


Hst Pancet Program: A Complete Near-Uv To Infrared Transmission Spectrum For The Hot Jupiter Wasp-79b, Alexander D. Rathcke, Ryan J. Macdonald, Joanna K. Barstow, Jayesh M. Goyal, Mercedes Lopez-Morales, João M. Mendonça, Jorge Sanz-Forcada, Gregory W. Henry, David K. Sing, Munazza K. Alam, Nikole K. Lewis, Katy L. Chubb, Jake Taylor, Nikolay Nikolov, Lars A. Buchhave Sep 2021

Hst Pancet Program: A Complete Near-Uv To Infrared Transmission Spectrum For The Hot Jupiter Wasp-79b, Alexander D. Rathcke, Ryan J. Macdonald, Joanna K. Barstow, Jayesh M. Goyal, Mercedes Lopez-Morales, João M. Mendonça, Jorge Sanz-Forcada, Gregory W. Henry, David K. Sing, Munazza K. Alam, Nikole K. Lewis, Katy L. Chubb, Jake Taylor, Nikolay Nikolov, Lars A. Buchhave

Information Systems and Engineering Management Research Publications

We present a new optical transmission spectrum of the hot Jupiter WASP-79b. We observed three transits with the STIS instrument mounted on the Hubble Space Telescope (HST), spanning 0.3–1.0 μm. Combining these transits with previous observations, we construct a complete 0.3–5.0 μm transmission spectrum of WASP-79b. Both HST and ground-based observations show decreasing transit depths toward blue wavelengths, contrary to expectations from Rayleigh scattering or hazes. We infer atmospheric and stellar properties from the full near-UV to infrared transmission spectrum of WASP-79b using three independent retrieval codes, all of which yield consistent results. Our retrievals confirm previous detections of H2O …


Erratum: Searches For Continuous Gravitational Waves From Nine Young Supernova Remnants (Apj (2015) 813 (39) Doi: 10.1088/0004-637x/813/1/39), J. Aasi, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, A. Ain, P. Ajith, Tiffany Z. Summerscales Sep 2021

Erratum: Searches For Continuous Gravitational Waves From Nine Young Supernova Remnants (Apj (2015) 813 (39) Doi: 10.1088/0004-637x/813/1/39), J. Aasi, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, A. Ain, P. Ajith, Tiffany Z. Summerscales

Faculty Publications

Equation (7) of the published article (Aasi et al. 2015) is in error; it should read (Equation presented). The upper limits on ò presented in the published article are unaffected by this error. Equation (8) of the published article is in error; it should read (Equation presented) The upper limits on α presented in Figure 3 and Table 4 of the published article were computed incorrectly. The revised Figure 3 (bottom) shows the corrected upper limits on α for the G266.2-1.2 (Vela Jr.) wide search. The revised Table 4 is provided here. The correct lowest upper limit on α (quoted …


Strong Inclination Pacing Of Climate In Late Triassic Low Latitudes Revealed By The Earth-Saturn Tilt Cycle, Miranda Margulis-Ohnuma, Jessica Whiteside, Paul Olsen Sep 2021

Strong Inclination Pacing Of Climate In Late Triassic Low Latitudes Revealed By The Earth-Saturn Tilt Cycle, Miranda Margulis-Ohnuma, Jessica Whiteside, Paul Olsen

The Yale Undergraduate Research Journal

Gravitational interactions among masses in the solar system are recorded in Earth’s paleoclimate history because variations in the geometry of Earth’s orbit and axial orientation modulate insolation. However, astronomical models are unreliable before ~50 Ma due to the chaotic nature of the solar system and therefore must be constrained using geological observations. Here, we use environmental proxies from paleo-tropical Late Triassic lake deposits of the Newark Rift Basin to identify and tune to previously undescribed strong variations in orbital inclination. Tuning to the 173 kyr Earth-Saturn inclination cycle, theoretically stable due to the high mass of Saturn, reveals both other …


Mapping The Gravitational-Wave Sky With Lisa: A Bayesian Spherical Harmonic Approach, Sharan Banagiri, Alexander Criswell, Tommy Kuan, Vuk Mandic, Joseph D. Romano, Stephen R. Taylor Sep 2021

Mapping The Gravitational-Wave Sky With Lisa: A Bayesian Spherical Harmonic Approach, Sharan Banagiri, Alexander Criswell, Tommy Kuan, Vuk Mandic, Joseph D. Romano, Stephen R. Taylor

Physics & Astronomy Faculty Publications

The millihertz gravitational-wave frequency band is expected to contain a rich symphony of signals with sources ranging from Galactic white dwarf binaries to extreme mass ratio inspirals. Many of these gravitational-wave signals will not be individually resolvable. Instead, they will incoherently add to produce stochastic gravitational-wave confusion noise whose frequency content will be governed by the dynamics of the sources. The angular structure of the power of the confusion noise will be modulated by the distribution of the sources across the sky. Measurement of this structure can yield important information about the distribution of sources on Galactic and extragalactic scales, …


Direct H-He Chemical Association In Superionic Feo2H2He At Deep-Earth Conditions, Jurong Zhang, Hanyu Liu, Yanming Ma, Changfeng Chen Sep 2021

Direct H-He Chemical Association In Superionic Feo2H2He At Deep-Earth Conditions, Jurong Zhang, Hanyu Liu, Yanming Ma, Changfeng Chen

Physics & Astronomy Faculty Research

Hydrogen and helium are known to play crucial roles in geological and astrophysical environments; however, they are inert toward each other across wide pressure-temperature (P-T) conditions. Given their prominent presence and influence on the formation and evolution of celestial bodies, it is of fundamental interest to explore the nature of interactions between hydrogen and helium. Using an advanced crystal structure search method, we have identified a quaternary compound FeO2H2He stabilized in a wide range of P-T conditions. Ab initio molecular dynamics simulations further reveal a novel superionic state of FeO2H2He hosting liquid-like …


Measurement Of The Masses And Widths Of The Σc (2455)+ And Σc (2520)+ Baryons, J. Yelton, I. Adachi, J. K. Ahn, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka Sep 2021

Measurement Of The Masses And Widths Of The Σc (2455)+ And Σc (2520)+ Baryons, J. Yelton, I. Adachi, J. K. Ahn, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka

Faculty and Student Publications

Using 980 fb-1 of data collected with the Belle detector operating at the KEKB asymmetric-energy e+e- collider, we report the measurements of the masses, and the first measurements of the instrinsic widths, of the ςc(2455)+ and ςc(2520)+ charmed baryons. We find M(ςc(2455)+)-M(Λc+)=166.17±0.05-0.07+0.16 MeV/c2, Γ(ςc(2455)+)=2.3±0.3±0.3 MeV/c2, M(ςc(2520)+)-M(Λc+)=230.9±0.5-0.1+0.5 MeV/c2, and Γ(ςc(2520)+)=17.2-2.1-0.7+2.3+3.1 MeV/c2, where the uncertainties are statistical and systematic, respectively. These measurements can be used to test models of the underlying quark structure of the ςc states.