Search

Your search keyword '"Gregory Martinez"' showing total 8 results
Start Over Author "Gregory Martinez"
8 results on '"Gregory Martinez"'

1. Orbital and Atmospheric Characterization of the 1RXS J034231.8+121622 System using High-resolution Spectroscopy Confirms that the Companion is a Low-mass Star

Author

Clarissa R. Do Ó, Ben Sappey, Quinn M. Konopacky, Jean-Baptiste Ruffio, Kelly K. O’Neil, Tuan Do, Gregory Martinez, Travis S. Barman, Jayke S. Nguyen, Jerry W. Xuan, Christopher A. Theissen, Sarah Blunt, William Thompson, Chih-Chun Hsu, Ashley Baker, Randall Bartos, Geoffrey A. Blake, Benjamin Calvin, Sylvain Cetre, Jacques-Robert Delorme, Greg Doppmann, Daniel Echeverri, Luke Finnerty, Michael P. Fitzgerald, Julie Inglis, Nemanja Jovanovic, Ronald A. López, Dimitri Mawet, Evan Morris, Jacklyn Pezzato, Tobias Schofield, Andrew Skemer, J. Kent Wallace, Jason J. Wang, Ji Wang, and Joshua Liberman

Subjects
Brown dwarfs, Direct imaging, High resolution spectroscopy, Exoplanets, Binary stars, Orbit determination, Astronomy, QB1-991
Abstract

The 1RXS J034231.8+121622 system consists of an M dwarf primary and a directly imaged low-mass stellar companion. We use high-resolution spectroscopic data from Keck/KPIC to estimate the objects' atmospheric parameters and radial velocities (RVs). Using PHOENIX stellar models, we find that the primary has a temperature of 3460 ± 50 K and a metallicity of 0.16 ± 0.04, while the secondary has a temperature of 2510 ± 50 K and a metallicity of ${0.13}_{-0.11}^{+0.12}$ . Recent work suggests this system is associated with the Hyades, giving it an older age than previous estimates. Both metallicities agree with current Hyades [Fe/H] measurements (0.11–0.21). Using stellar evolutionary models, we obtain significantly higher masses for the objects, 0.30 ± 0.15 M _⊙ and 0.08 ± 0.01 M _⊙ (84 ± 11 M _Jup ), respectively. Using the RVs and a new astrometry point from Keck/NIRC2, we find that the system is likely an edge-on, moderately eccentric ( ${0.41}_{-0.08}^{+0.27}$ ) configuration. We also estimate the C/O ratio of both objects using custom grid models, obtaining 0.42 ± 0.10 (primary) and 0.55 ± 0.10 (companion). From these results, we confirm that this system most likely went through a binary star formation process in the Hyades. The significant changes in this system's parameters since its discovery highlight the importance of high-resolution spectroscopy for both orbital and atmospheric characterization of directly imaged companions.

Published
2024
Full Text
View/download PDF

3. Kinematics and Feedback in H ii Regions in the Dwarf Starburst Galaxy IC 10

Author

Maren Cosens, Shelley A. Wright, Norman Murray, Lee Armus, Karin Sandstrom, Tuan Do, Kirsten Larson, Gregory Martinez, Sanchit Sabhlok, Andrey Vayner, and James Wiley

Subjects
Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract

We present a survey of the central region of the nearest starburst galaxy, IC 10, using the W. M. Keck Observatory Keck Cosmic Web Imager (KCWI) at high spectral and spatial resolution. We map the central starburst of IC 10 to sample the kinematic and ionization properties of the individual star-forming regions. Using the low spectral resolution mode of KCWI we map the oxygen abundance and with the high spectral resolution mode we identify 46 individual H II regions. These H II regions have an average radius of 4.0 pc, star formation rate $\sim1.3\times10^{-4}$ M$_\odot$ yr$^{-1}$, and velocity dispersion $\sim$16 km s$^{-1}$. None of the H II regions appear to be virialized ($\rm α_{vir}>>1$), and, on average, they show evidence of ongoing expansion. IC 10's H II regions are offset from the star forming region size-luminosity scaling relationships, as well as Larson's Law that relates size and velocity dispersion. We investigate the balance of inward and outward pressure, $\rm P_{in}$ and $\rm P_{out}$, finding $\rm P_{out}>P_{in}$ in 89% of H II regions, indicating feedback driven expansion even in these low mass H II regions. We find warm gas pressure ($\rm P_{gas}$) provides the dominant contribution to the outward pressure ($\rm P_{out}$). This counteracts the inward pressure which is dominated by turbulence in the surrounding gas rather than self-gravity. Five H II regions show evidence of outflows which are most likely supported by either stellar winds (2 regions) or champagne flows (3 regions). These observations provide new insights into the state of the star-forming regions in IC 10 and negative feedback from low mass clusters., 57 pages, 35 figures, 9 tables, accepted for publication in The Astrophysical Journal

Published
2022

4. Pipe Land Transportation Through South America Andes/Cordillera: Company Bolivie, Incahuasi Project Phase 1

Author

Gregory Martinez

Subjects
Phase (matter), Physical geography, Geology
Abstract

The Company project, located in Bolivia, was implemented in 2014. The project is a green field development of three wells connected to a Central Processing Facility, including export pipelines and flowlines (gas & condensate). During the construction phase, the Project had to transfer 8883 pipes for gas export lines and flow lines that represented a total weight of more than 30 000 Tons from Chile to Bolivia. The World Health Organisation's Global Status Report on Road Safety (2013) explained that Bolivia had a road traffic death rate of 19 per 100 000 population (France= 6).The hazard due to Road transportation was identified at early stage of the project sanction and was classified as Major Operational Risk. The challenge was to ensure a high safety level along the 1478 km transportation route. The Cordillera Occidental geographical context and environmental conditions create one of the most dangerous roads in the world. The objective defined by the Project Management Team was to achieve zero accidents in pipe transport. Project team reinforced contractual HSE aspects with strong requirements and expectations in transportation management (Not only for the Contractor but also for their subcontractors and suppliers). A Road Safety specialist was contracted to join the Project HSE Team in order to prepare, assist and monitor the land transportation of pipes by road jointly with the Contractor. Key documents prepared and approved with the contractors were the HSE Plan and Transportation & Lifting Plan. Within these documents, specific elements of focus included (but not limited to): –Journey Management–Transportation and offloading pipe Analysis–Road Traffic study–Route Risk Analysis–Control/Checking points before critical routes–Vehicles inspection and approval by 3rd Party–Monitoring and tracking of vehicles IVMS (In Vehicle Monitoring System)–3rd party training of all drivers (244). The INCAHUASI Project successfully reached the HSE target for LLI pipes supply: Zero accidents during 67 weekly trips covering a distance of 4 million kilometers over the 5-month campaign. This is due to rigorous compliance and good co-operation of the workforce, Leadership & Commitment of Management from the Company and above all, its Partners.

Published
2020

5. Development of the project-level Women’s Empowerment in Agriculture Index (pro-WEAI)

Author

Emily Myers; Audrey Pereira; Anika Hannan; Laurie James-Hawkins; Sunny Kim; Shalini Roy; Marlène Elias; Annet Mulema; Deborah Rubin; Yuk Fai Cheong; Cheryl Doss; Lauren Maxwell; Akhter Ahmed; Masuma Younus; Alan de Brauw; Amita Dey; Berber Kramer; Benjamin Crookston; Megan Gash; Bobbi Gray; Pepijn Schreinemachers; Caroline Sobgui; Sarah Janzen; Neena Joshi; Nicholas Magnan; Rajendra Pradhan; Sudhindra Sharma; Sophie Theis; Marc Bellemare; Bart Casier; Susan James; Brooke Krause; Mathias Lardinois; Aine McCarthy; Sabine Gabrysch; Sheela Sinharoy; Jillian Waid; Amanda Wendt; Aulo Gelli; Melissa Hidrobo; Sita Zougouri; Silvia Alonso; Alessandra Galiè; Tasokwa Kakota; Jef Leroy; Giordano Palloni; Elizabeth Bryan; Brian Kiger; Dawit Mekonnen; Mamun Miah; Saiqa Siraj; Mihret Alemu; Brenda Boonabaana; Susan Kaaria; Vanya Slavchevska; Erdgin Mane; Avijit Choudhury; Neha Kumar; Kalyani Raghunathan, Malapit, Hazel J.; Quisumbing, Agnes R.; Meinzen-Dick, Ruth Suseela; Seymour, Gregory; Martinez, Elena M.; Heckert, Jessica; Rubin, Deborah; Vaz, Ana; Yount, Kathryn M.; Gender Agriculture Assets Project Phase 2 (GAAP2) Study Team, http://orcid.org/0000-0002-7394-8797 Malapit, Hazel; http://orcid.org/0000-0002-5429-1857 Quisumbing, Agnes; http://orcid.org/0000-0003-4782-3074 Meinzen-Dick, Ruth; http://orcid.org/0000-0002-2213-0450 Seymour, Gregory; https://orcid.org/0000-0001-9800-6651 Martinez, Elena; http://orcid.org/0000-0002-3022-8298 Heckert, Jessica; http://orcid.org/0000-0002-0112-502X Ahmed, A.; http://orcid.org/0000-0002-5045-8939 de Brauw, Alan; https://orcid.org/0000-0001-7982-7454 Pereira, Audrey; http://orcid.org/0000-0003-4977-2549 Gelli, Aulo; http://orcid.org/0000-0001-7644-6613 Kramer, Berber; http://orcid.org/0000-0003-3642-3497 Mekonnen, Dawit; http://orcid.org/0000-0002-0906-222X Bryan, Elizabeth; https://orcid.org/0000-0003-3599-5856 Myers, Emily Camille; http://orcid.org/0000-0002-2213-0450 Seymour, Gregory; http://orcid.org/0000-0001-9371-3832 Leroy, Jef; http://orcid.org/0000-0002-4705-4351 Raghunathan, Kalyani; http://orcid.org/0000-0003-2121-9522 Hidrobo, Melissa; http://orcid.org/0000-0001-7982-3277 Kumar, Neha; http://orcid.org/0000-0001-8053-1650 Roy, Shalini; http://orcid.org/0000-0003-3960-3354 Kim, Sunny, Emily Myers; Audrey Pereira; Anika Hannan; Laurie James-Hawkins; Sunny Kim; Shalini Roy; Marlène Elias; Annet Mulema; Deborah Rubin; Yuk Fai Cheong; Cheryl Doss; Lauren Maxwell; Akhter Ahmed; Masuma Younus; Alan de Brauw; Amita Dey; Berber Kramer; Benjamin Crookston; Megan Gash; Bobbi Gray; Pepijn Schreinemachers; Caroline Sobgui; Sarah Janzen; Neena Joshi; Nicholas Magnan; Rajendra Pradhan; Sudhindra Sharma; Sophie Theis; Marc Bellemare; Bart Casier; Susan James; Brooke Krause; Mathias Lardinois; Aine McCarthy; Sabine Gabrysch; Sheela Sinharoy; Jillian Waid; Amanda Wendt; Aulo Gelli; Melissa Hidrobo; Sita Zougouri; Silvia Alonso; Alessandra Galiè; Tasokwa Kakota; Jef Leroy; Giordano Palloni; Elizabeth Bryan; Brian Kiger; Dawit Mekonnen; Mamun Miah; Saiqa Siraj; Mihret Alemu; Brenda Boonabaana; Susan Kaaria; Vanya Slavchevska; Erdgin Mane; Avijit Choudhury; Neha Kumar; Kalyani Raghunathan, Malapit, Hazel J.; Quisumbing, Agnes R.; Meinzen-Dick, Ruth Suseela; Seymour, Gregory; Martinez, Elena M.; Heckert, Jessica; Rubin, Deborah; Vaz, Ana; Yount, Kathryn M.; Gender Agriculture Assets Project Phase 2 (GAAP2) Study Team, and http://orcid.org/0000-0002-7394-8797 Malapit, Hazel; http://orcid.org/0000-0002-5429-1857 Quisumbing, Agnes; http://orcid.org/0000-0003-4782-3074 Meinzen-Dick, Ruth; http://orcid.org/0000-0002-2213-0450 Seymour, Gregory; https://orcid.org/0000-0001-9800-6651 Martinez, Elena; http://orcid.org/0000-0002-3022-8298 Heckert, Jessica; http://orcid.org/0000-0002-0112-502X Ahmed, A.; http://orcid.org/0000-0002-5045-8939 de Brauw, Alan; https://orcid.org/0000-0001-7982-7454 Pereira, Audrey; http://orcid.org/0000-0003-4977-2549 Gelli, Aulo; http://orcid.org/0000-0001-7644-6613 Kramer, Berber; http://orcid.org/0000-0003-3642-3497 Mekonnen, Dawit; http://orcid.org/0000-0002-0906-222X Bryan, Elizabeth; https://orcid.org/0000-0003-3599-5856 Myers, Emily Camille; http://orcid.org/0000-0002-2213-0450 Seymour, Gregory; http://orcid.org/0000-0001-9371-3832 Leroy, Jef; http://orcid.org/0000-0002-4705-4351 Raghunathan, Kalyani; http://orcid.org/0000-0003-2121-9522 Hidrobo, Melissa; http://orcid.org/0000-0001-7982-3277 Kumar, Neha; http://orcid.org/0000-0001-8053-1650 Roy, Shalini; http://orcid.org/0000-0003-3960-3354 Kim, Sunny

Abstract

PR, IFPRI3; ISI; CRP4; GAAP; DCA, PHND; EPTD; A4NH, CGIAR Research Program on Agriculture for Nutrition and Health (A4NH), With growing commitment to women’s empowerment by agricultural development agencies, sound methods and indicators to measure women’s empowerment are needed to learn which types of projects or project-implementation strategies do and do not work to empower women. The Women’s Empowerment in Agriculture Index (WEAI), which has been widely used, requires adaptation to meet the need for monitoring projects and assessing their impacts. In this paper, the authors describe the adaptation and validation of a project-level WEAI (or pro-WEAI) that agricultural development projects can use to identify key areas of women’s (and men’s) disempowerment, design appropriate strategies to address identified deficiencies, and monitor project outcomes related to women’s empowerment.

Published
2019

6. Development of the project-level Women’s Empowerment in Agriculture Index (pro-WEAI)

Author

Gender, Agriculture, and Assets Project, Phase 2 (GAAP2) Study Team, Malapit, Hazel J.; Quisumbing, Agnes R.; Meinzen-Dick, Ruth Suseela; Seymour, Gregory; Martinez, Elena M.; Heckert, Jessica; Rubin, Deborah; Vaz, Ana; Yount, Kathryn M., http://orcid.org/0000-0002-7394-8797 Malapit, Hazel; http://orcid.org/0000-0002-5429-1857 Quisumbing, Agnes; http://orcid.org/0000-0003-4782-3074 Meinzen-Dick, Ruth; http://orcid.org/0000-0002-2213-0450 Seymour, Gregory; http://orcid.org/0000-0002-3022-8298 Heckert, Jessica; https://orcid.org/0000-0001-9800-6651 Martinez, Elena, Gender, Agriculture, and Assets Project, Phase 2 (GAAP2) Study Team, Malapit, Hazel J.; Quisumbing, Agnes R.; Meinzen-Dick, Ruth Suseela; Seymour, Gregory; Martinez, Elena M.; Heckert, Jessica; Rubin, Deborah; Vaz, Ana; Yount, Kathryn M., and http://orcid.org/0000-0002-7394-8797 Malapit, Hazel; http://orcid.org/0000-0002-5429-1857 Quisumbing, Agnes; http://orcid.org/0000-0003-4782-3074 Meinzen-Dick, Ruth; http://orcid.org/0000-0002-2213-0450 Seymour, Gregory; http://orcid.org/0000-0002-3022-8298 Heckert, Jessica; https://orcid.org/0000-0001-9800-6651 Martinez, Elena

Subjects
agency; multidimensional measurement; Women's empowerment
Abstract

Non-PR, IFPRI1; CRP4; Women’s Empowerment in Agriculture Index; GAAP; G Cross-cutting gender theme; Capacity Strengthening, PHND; EPTD; A4NH, CGIAR Research Program on Agriculture for Nutrition and Health (A4NH), In this paper, the authors describe the adaptation and validation of a project-level WEAI (or pro-WEAI) that agricultural development projects can use to identify key areas of women’s (and men’s) disempowerment, design appropriate strategies to address identified deficiencies, and monitor project outcomes related to women’s empowerment. The 12 pro-WEAI indicators are mapped to three domains: intrinsic agency (power within), instrumental agency (power to), and collective agency (power with). A gender parity index compares the empowerment scores of men and women in the same household. The authors describe the development of pro-WEAI, including: (1) pro-WEAI’s distinctiveness from other versions of the WEAI; (2) the process of piloting pro-WEAI in 13 agricultural development projects during the Gender, Agriculture, and Assets Project, phase 2 (GAAP2); (3) analysis of quantitative data from the GAAP2 projects, including intrahousehold patterns of empowerment; and (4) a summary of the findings from the qualitative work exploring concepts of women’s empowerment in the project sites. The paper concludes with a discussion of lessons learned from pro-WEAI and possibilities for further development of empowerment metrics.

Published
2019

7. Why Did They Come Here? –The Influences and Expectations of First-Year Students’ College Experience

Author

Casey Alexander Fuhriman, Carrie Semmelroth, Gregory Martinez, Matthew Featherstone, Louis S. Nadelson, and Andrew Sell

Subjects
media_common.quotation_subject, Perception, Mathematics education, Attendance, Institution, Racial differences, Statistical analysis, Positive perception, Psychology, Educational attainment, Reputation, media_common
Abstract

Students’ expectations and experiences with university life are influenced by a number of variables. Many universities develop programs or promote aspects of existing programs to market the university’s image. This research was motivated by our desire to determine the relationships between first-year students’ college expectations and experiences, their awareness of the university’s programming and projected image, the influence of the programming and image on their decision to attend the institution, and the students’ personal characteristics. Our survey of 351 first-year students revealed positive perceptions of their university expectations and experiences, a mixture of influences on their decision to attend the university, and correlations between program awareness and the influence on students’ university attendance. We also uncovered a number of relationships between expectations, experience, and perceptions of influences with the personal characteristics of the students. Implications, directions for future research, and limitations are discussed.

Published
2013

8. Size–Luminosity Scaling Relations of Local and Distant Star-forming Regions.

Author

Maren Cosens, Shelley A. Wright, Etsuko Mieda, Norman Murray, Lee Armus, Tuan Do, James E. Larkin, Kirsten Larson, Gregory Martinez, Gregory Walth, and Andrey Vayner

Subjects
STAR formation, LUMINOSITY, BAYESIAN analysis, STELLAR mass, MARKOV chain Monte Carlo, GALACTIC redshift
Abstract

We investigate star-forming scaling relations using Bayesian inference on a comprehensive data sample of low- (z < 0.1) and high-redshift (1 < z < 5) star-forming regions. This full data set spans a wide range of host galaxy stellar mass (M* ∼ 106–1011 ) and clump star formation rates (SFR ∼ 10−5 −102 yr−1). We fit the power-law relationship between the size () and luminosity () of the star-forming clumps using the Bayesian statistical modeling tool Stan, which makes use of Markov Chain Monte Carlo (MCMC) sampling techniques. Trends in the scaling relationship are explored for the full sample and subsets based on redshift and selection effects between samples. In our investigation, we find neither evidence of redshift evolution of the size–luminosity scaling relationship nor a difference in slope between lensed and unlensed data. There is evidence of a break in the scaling relationship between high and low SFR surface density () clumps. The size–luminosity power-law fit results are ∼ 2.8 and ∼ 1.7 for low and high clumps, respectively. We present a model where star-forming clumps form at locations of gravitational instability and produce an ionized region represented by the Strömgren radius. A radius smaller than the scale height of the disk results in a scaling relationship of L ∝ r3 (high clumps), and a scaling of L ∝ r2 (low clumps) if the radius is larger than the disk scale height. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results