202 research outputs found
OGLE-2016-BLG-1227L: A Wide-separation Planet from a Very Short-timescale Microlensing Event
We present the analysis of the microlensing event OGLE-2016-BLG-1227. The light curve of this short-duration event appears to be a single-lens event affected by severe finite-source effects. Analysis of the light curve based on single-lens single-source (1L1S) modeling yields very small values of the event timescale, t_E ⌠3.5 days, and the angular Einstein radius, Ξ_E ⌠0.009 mas, making the lens a candidate of a free-floating planet. Close inspection reveals that the 1L1S solution leaves small residuals with amplitude ÎI âČ 0.03 mag. We find that the residuals are explained by the existence of an additional widely-separated heavier lens component, indicating that the lens is a wide-separation planetary system rather than a free-floating planet. From Bayesian analysis, it is estimated that the planet has a mass of _p = 0.79^(+1.30)_(â0.39) M_J and it is orbiting a low-mass host star with a mass of M_(host) = 0.10+0.17â0.05 M_â located with a projected separation of a_ = 3.4^(+2.1)_(â1.0) au. The planetary system is located in the Galactic bulge with a line-of-sight separation from the source star of D_(LS) = 1.21^(+0.96)_(â0.63) kpc. The event shows that there are a range of deviations in the signatures of host stars for apparently isolated planetary lensing events and that it is possible to identify a host even when a deviation is subtle
KMT-2018-BLG-1292: A Super-Jovian Microlens Planet in the Galactic Plane
We report the discovery of KMT-2018-BLG-1292Lb, a super-Jovian planet orbiting an F or G dwarf , which lies physically within {\cal O}(10\,\pc) of the
Galactic plane. The source star is a heavily extincted luminous
giant that has the lowest Galactic latitude, , of any planetary
microlensing event. The relatively blue blended light is almost certainly
either the host or its binary companion, with the first explanation being
substantially more likely. This blend dominates the light at band and
completely dominates at and bands. Hence, the lens system can be probed
by follow-up observations immediately, i.e., long before the lens system and
the source separate due to their relative proper motion. The system is well
characterized despite the low cadence -- of
observations and short viewing windows near the end of the bulge season. This
suggests that optical microlensing planet searches can be extended to the
Galactic plane at relatively modest cost.Comment: 35 pages, 3 Tables, 8 figure
OGLE-2018-BLG-0532Lb: Cold Neptune With Possible Jovian Sibling
We report the discovery of the planet OGLE-2018-BLG-0532Lb, with very obvious
signatures in the light curve that lead to an estimate of the planet-host mass
ratio . Although there are
no obvious systematic residuals to this double-lens/single-source (2L1S) fit,
we find that can be significantly improved by adding either a third
lens (3L1S, ) or second source (2L2S, ) to
the lens-source geometry. After thorough investigation, we conclude that we
cannot decisively distinguish between these two scenarios and therefore focus
on the robustly-detected planet. However, given the possible presence of a
second planet, we investigate to what degree and with what probability such
additional planets may affect seemingly single-planet light curves. Our best
estimates for the properties of the lens star and the secure planet are: a host
mass , system distance kpc and planet mass
with projected separation au.
However, there is a relatively bright (and also relatively blue) star
projected within mas of the lens, and if future high-resolution images
show that this is coincident with the lens, then it is possible that it is the
lens, in which case, the lens would be both more massive and more distant than
the best-estimated values above.Comment: 48 pages, 9 figures, 7 table
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Parental Monitoring of Childrenâs Media Consumption: The Long-term Influences on Body Mass Index in Children
IMPORTANCE: Although childrenâs media consumption has been one of the most robust risk factors for childhood obesity, effects of specific parenting influences, such as parental media monitoring, have not been effectively investigated.
OBJECTIVES: This study examined the potential influences of maternal and paternal monitoring of child media exposure and childrenâs general activities on childrenâs BMI in middle childhood.
DESIGN: A longitudinal study, taken from a subsample of the Three Generational Study, with assessments at childrenâs ages of 5, 7, and/or 9 years collected from 1998-2012.
SETTING: The Three Generational Study, a predominantly Caucasian, Pacific-Northwest U.S. community sample (overall participation rate 90%).
PARTICIPANTS: Analyses included 112 mothers, 103 fathers and their 213 children (55% girls) at ages 5, 7, and/or 9 years. Participation rates ranged from 67% to 72% of all eligible Three Generational Study children across the three assessments.
MAIN EXPOSURES: Parents reported on their general monitoring of their children (whereabouts and activities), specific monitoring of child media exposure, childrenâs participation in sports and recreational activities, childrenâs media time (hours/week), annual income, and education level. Parental BMI was recorded.
MAIN OUTCOME MEASURE: Predictions to level and change in child BMI z scores were tested.
RESULTS: Linear mixed-effects modeling indicated that more maternal, but not paternal, monitoring of child media exposure predicted lower child BMI z scores at age 7 years (95% CI, -.39 â -.07) and less steeply increasing child BMI z scores from ages 5-9 years (95% CI, -.11 â -.01). These effects held when controlling for more general parental monitoring, and parent BMI, income and education. Results supported that the significant negative effect of maternal media monitoring on childrenâs BMI z scores at age 7 years was marginally accounted for by the effect of child media time. The maternal media monitoring effect on childrenâs BMI z score slopes remained significant once adjusting for childrenâs media time, and sports and recreational activity.
CONCLUSIONS: This study suggests that parental behaviors related to childrenâs media consumption may have long-term impacts on childrenâs BMI in middle childhood. The results underscore the importance of targeting parental media monitoring in efforts to prevent childhood obesity
A noncanonical role for the engulfment gene ELMO1 in neutrophils that promotes inflammatory arthritis
Rheumatoid arthritis is characterized by progressive joint inflammation and affects similar to 1% of the human population. We noted single-nucleotide polymorphisms (SNPs) in the apoptotic cell-engulfment genes ELMO1, DOCK2, and RAC1 linked to rheumatoid arthritis. As ELMO1 promotes cytoskeletal reorganization during engulfment, we hypothesized that ELMO1 loss would worsen inflammatory arthritis. Surprisingly, Elmo1-deficient mice showed reduced joint inflammation in acute and chronic arthritis models. Genetic and cell-biology studies revealed that ELMO1 associates with receptors linked to neutrophil function in arthritis and regulates activation and early neutrophil recruitment to the joints, without general inhibition of inflammatory responses. Further, neutrophils from the peripheral blood of human donors that carry the SNP in ELMO1 associated with arthritis display increased migratory capacity, whereas ELMO1 knockdown reduces human neutrophil migration to chemokines linked to arthritis. These data identify 'noncanonical' roles for ELMO1 as an important cytoplasmic regulator of specific neutrophil receptors and promoter of arthritis
Spectroscopic Mass and Host-star Metallicity Measurements for Newly Discovered Microlensing Planet OGLE-2018-BLG-0740Lb
We report the discovery of the microlensing planet OGLE-2018-BLG-0740Lb. The
planet is detected with a very strong signal of , but
the interpretation of the signal suffers from two types of degeneracies. One
type is caused by the previously known close/wide degeneracy, and the other is
caused by an ambiguity between two solutions, in which one solution requires to
incorporate finite-source effects, while the other solution is consistent with
a point-source interpretation. Although difficult to be firmly resolved based
on only the photometric data, the degeneracy is resolved in strong favor of the
point-source solution with the additional external information obtained from
astrometric and spectroscopic observations. The small astrometric offset
between the source and baseline object supports that the blend is the lens and
this interpretation is further secured by the consistency of the spectroscopic
distance estimate of the blend with the lensing parameters of the point-source
solution. The estimated mass of the host is and the mass
of the planet is (close solution) or (wide solution) and the lens is located at a distance of ~kpc.
The bright nature of the lens, with (), combined with
its dominance of the observed flux suggest that radial-velocity (RV) follow-up
observations of the lens can be done using high-resolution spectrometers
mounted on large telescopes, e.g., VLT/ESPRESSO, and this can potentially not
only measure the period and eccentricity of the planet but also probe for
close-in planets. We estimate that the expected RV amplitude would be .Comment: 12 pages, 11 figures, 4 table
OGLE-2018-BLG-0022: First Prediction of an Astrometric Microlensing Signal from a Photometric Microlensing Event
In this work, we present the analysis of the binary microlensing event
OGLE-2018-BLG-0022 that is detected toward the Galactic bulge field. The dense
and continuous coverage with the high-quality photometry data from ground-based
observations combined with the space-based {\it Spitzer} observations of this
long time-scale event enables us to uniquely determine the masses and of the individual lens components.
Because the lens-source relative parallax and the vector lens-source relative
proper motion are unambiguously determined, we can likewise unambiguously
predict the astrometric offset between the light centroid of the magnified
images (as observed by the {\it Gaia} satellite) and the true position of the
source. This prediction can be tested when the individual-epoch {\it Gaia}
astrometric measurements are released.Comment: 10 pages, 10 figures, 4 table
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