37 research outputs found
The isolation and identification of the P-component of normal human plasma proteins (Short Communication)
Two warm, low-density sub-Jovian planets orbiting bright stars in K2 campaigns 13 and 14
We report the discovery of two planets transiting the bright stars HD 89345
(EPIC 248777106, , ) in K2 Campaign 14 and HD 286123 (EPIC
247098361, , ) in K2 Campaign 13. Both stars are G-type
stars, one of which is at or near the end of its main sequence lifetime, and
the other that is just over halfway through its main sequence lifetime. HD
89345 hosts a warm sub-Saturn (0.66 , 0.11 , K)
in an 11.81-day orbit. The planet is similar in size to WASP-107b, which falls
in the transition region between ice giants and gas giants. HD 286123 hosts a
Jupiter-sized, low-mass planet (1.06 , 0.39 , K)
in an 11.17-day, mildly eccentric orbit, with . Given that
they orbit relatively evolved main-sequence stars and have orbital periods
longer than 10 days, these planets are interesting candidates for studies of
gas planet evolution, migration, and (potentially) re-inflation. Both planets
have spent their entire lifetimes near the proposed stellar irradiation
threshold at which giant planets become inflated, and neither shows any sign of
radius inflation. They probe the regime where inflation begins to become
noticeable and are valuable in constraining planet inflation models. In
addition, the brightness of the host stars, combined with large atmospheric
scale heights of the planets, makes these two systems favorable targets for
transit spectroscopy to study their atmospheres and perhaps provide insight
into the physical mechanisms that lead to inflated hot Jupiters.Comment: 16 pages, 12 figures; accepted for publication in A
275 Candidates and 149 Validated Planets Orbiting Bright Stars in K2 Campaigns 0-10
Since 2014, NASA's K2 mission has observed large portions of the ecliptic
plane in search of transiting planets and has detected hundreds of planet
candidates. With observations planned until at least early 2018, K2 will
continue to identify more planet candidates. We present here 275 planet
candidates observed during Campaigns 0-10 of the K2 mission that are orbiting
stars brighter than 13 mag (in Kepler band) and for which we have obtained
high-resolution spectra (R = 44,000). These candidates are analyzed using the
VESPA package (Morton 2012, 2015b) in order to calculate their false-positive
probabilities (FPP). We find that 149 candidates are validated with an FPP
lower than 0.1%, 39 of which were previously only candidates and 56 of which
were previously undetected. The processes of data reduction, candidate
identification, and statistical validation are described, and the demographics
of the candidates and newly validated planets are explored. We show tentative
evidence of a gap in the planet radius distribution of our candidate sample.
Comparing our sample to the Kepler candidate sample investigated by Fulton et
al. (2017), we conclude that more planets are required to quantitatively
confirm the gap with K2 candidates or validated planets. This work, in addition
to increasing the population of validated K2 planets by nearly 50% and
providing new targets for follow-up observations, will also serve as a
framework for validating candidates from upcoming K2 campaigns and the
Transiting Exoplanet Survey Satellite, expected to launch in 2018.Comment: Published in AJ, 47 pages, 18 figures, 7 tables, associated
supplementary dataset available at https://zenodo.org/record/116479
Another Shipment of Six Short-Period Giant Planets from TESS
We present the discovery and characterization of six short-period, transiting
giant planets from NASA's Transiting Exoplanet Survey Satellite (TESS) --
TOI-1811 (TIC 376524552), TOI-2025 (TIC 394050135), TOI-2145 (TIC 88992642),
TOI-2152 (TIC 395393265), TOI-2154 (TIC 428787891), & TOI-2497 (TIC 97568467).
All six planets orbit bright host stars (8.9 <G< 11.8, 7.7 <K< 10.1). Using a
combination of time-series photometric and spectroscopic follow-up observations
from the TESS Follow-up Observing Program (TFOP) Working Group, we have
determined that the planets are Jovian-sized (R = 1.00-1.45 R),
have masses ranging from 0.92 to 5.35 M, and orbit F, G, and K stars
(4753 T 7360 K). We detect a significant orbital eccentricity
for the three longest-period systems in our sample: TOI-2025 b (P = 8.872 days,
= ), TOI-2145 b (P = 10.261 days, =
), and TOI-2497 b (P = 10.656 days, =
). TOI-2145 b and TOI-2497 b both orbit subgiant host
stars (3.8 g 4.0), but these planets show no sign of inflation
despite very high levels of irradiation. The lack of inflation may be explained
by the high mass of the planets; M (TOI-2145
b) and M (TOI-2497 b). These six new discoveries
contribute to the larger community effort to use {\it TESS} to create a
magnitude-complete, self-consistent sample of giant planets with
well-determined parameters for future detailed studies.Comment: 20 Pages, 6 Figures, 8 Tables, Accepted by MNRA
275 Candidates and 149 Validated Planets Orbiting Bright Stars in K2 Campaigns 0–10
Since 2014, NASA's K2 mission has observed large portions of the ecliptic plane in search of transiting planets and has detected hundreds of planet candidates. With observations planned until at least early 2018, K2 will continue to identify more planet candidates. We present here 275 planet candidates observed during Campaigns 0–10 of the K2 mission that are orbiting stars brighter than 13 mag (in Kepler band) and for which we have obtained high-resolution spectra (R = 44,000). These candidates are analyzed using the vespa package in order to calculate their false-positive probabilities (FPP). We find that 149 candidates are validated with an FPP lower than 0.1%, 39 of which were previously only candidates and 56 of which were previously undetected. The processes of data reduction, candidate identification, and statistical validation are described, and the demographics of the candidates and newly validated planets are explored. We show tentative evidence of a gap in the planet radius distribution of our candidate sample. Comparing our sample to the Kepler candidate sample investigated by Fulton et al., we conclude that more planets are required to quantitatively confirm the gap with K2 candidates or validated planets. This work, in addition to increasing the population of validated K2 planets by nearly 50% and providing new targets for follow-up observations, will also serve as a framework for validating candidates from upcoming K2 campaigns and the Transiting Exoplanet Survey Satellite, expected to launch in 2018
The relationship of serum hexosamine, globulins and antibodies to experimental amyloidosis
Amyloid as a disease in human beings occurs not only de novo, but also secondary to a variety of chronic infectious diseases, to rheumatoid arthritis, and to multiple myeloma. These apparently unrelated diseases may, therefore, have some characteristics in common, as evidenced by their ability to produce amyloid. Knowledge of the specific biological alterations that are responsible for secondary amyloidosis may highlight certain factors common to these diverse primary diseases as well as aid in elucidating the basic physiological alterations responsible for the disease process of rheumatoid arthritis, which is complicated by a high incidence of amyloidosis. Secondary amyloidosis has been produced in experimental animals by numerous workers (1-11). Whether the amyloid produced in experimental animals is identical in chemical structure and pathogenesis to the primary and secondary amyloid found in human beings has not been established. Though several workers have pointed out the frequency with which hyperglobulinemia occurs (2, 3, 7, 12, 13), others have demonstrated that alterations in blood lipoproteins (7) and elevation of the serum hexosamine (14) occur. On the basis of these observations it has been suggested that amyloid may be the product of an antigen-antibody precipitate (13, 15, 16) or the indirect result of other immunological reactions