Ongoing astrometric microlensing events from VVV and Gaia

6 pages, 2 figures, accepted MNRAS LettersWe extend predictive microlensing event searches using the Vista Variables in the Via Lactea survey and the second Gaia data release. We identify two events with maxima in 2019 that require urgent follow-up. First, we predict that the nearby M2 dwarf L 338-152 will align with a background source with a closest approach of $35^{+35}_{-23}$ mas on 2019 November $16^{+28}_{-27}$ d. This will cause a peak astrometric shift and photometric amplification of the background source of $2.7^{+3.5}_{-1.5}$ mas and $5.6^{+143.2}_{-5.2}$ mmag respectively. This event should be astrometrically detectable by both the Hubble Space Telescope (HST) and the Spectro-Polarimetric High-contrast Exoplanet Research instrument on the Very Large Telescope. Secondly, we predict the likely K dwarf NLTT 45128 will lens a background source with a closest approach of $105.3^{+12.2}_{-11.7}$ mas on 2019 September $26^{+15}_{-15}$ d. This will produce a peak astrometric shift of $0.329^{+0.065}_{-0.059}$ mas. NLTT 45128 is only 3.6 magnitudes brighter than the background source which makes it an excellent candidate for follow-up with HST. Characterisation of these signals will allow direct gravitational masses to be inferred for both L 338-152 and NLTT 45128 with an estimated precision of $\sim9$ and $\sim13$ per cent respectively.Peer reviewedFinal Published versio

Landowner Characteristics Associated with Receiving Information About Invasive Plants and Implications for Outreach Providers

Based on a survey of woodland owners in West Virginia, we examined the possibility of differences in the characteristics of those who had and had not received information about local invasive plants and implications for outreach providers. Findings suggest that landowners who farmed on their property, held recreation objectives, and lived in the local area were significantly more likely than their counterparts to have received information. A majority of landowners with these characteristics, however, had not heard or read such information. Implications for expanding awareness through both traditional and non-traditional information channels are presented

Radial Redshift Space Distortions

The radial component of the peculiar velocities of galaxies cause displacements in their positions in redshift space. We study the effect of the peculiar velocities on the linear redshift space two point correlation function. Our analysis takes into account the radial nature of the redshift space distortions and it highlights the limitations of the plane parallel approximation. We consider the problem of determining the value of \beta and the real space two point correlation function from the linear redshift space two point correlation function. The inversion method proposed here takes into account the radial nature of the redshift space distortions and can be applied to magnitude limited redshift surveys that have only partial sky coverage.Comment: 26 pages including 11 figures, to appear in Ap

The Correlation Function in Redshift Space: General Formula with Wide-angle Effects and Cosmological Distortions

A general formula for the correlation function in redshift space is derived in linear theory. The formula simultaneously includes wide-angle effects and cosmological distortions. The formula is applicable to any pair with arbitrary angle $\theta$ between lines of sight, and arbitrary redshifts, $z_1$, $z_2$, which are not necessarily small. The effects of the spatial curvature both on geometry and on fluctuation spectrum are properly taken into account, and thus our formula holds in a Friedman-Lema\^{\i}tre universe with arbitrary cosmological parameters $\Omega_0$ and $\lambda_0$. We illustrate the pattern of the resulting correlation function with several models, and also show that validity region of the conventional distant observer approximation is $\theta \le 10^\circ$.Comment: 45 pages including 9 figures, To Appear in Astrophys. J. 535 (2000

Primordial Black Hole Dark Matter Simulations Using PopSyCLE

Primordial black holes (PBHs), theorized to have originated in the early universe, are speculated to be a viable form of dark matter. If they exist, they should be detectable through photometric and astrometric signals resulting from gravitational microlensing of stars in the Milky Way. Population Synthesis for Compact-object Lensing Events, or PopSyCLE, is a simulation code that enables users to simulate microlensing surveys, and is the first of its kind to include both photometric and astrometric microlensing effects, which are important for potential PBH detection and characterization. To estimate the number of observable PBH microlensing events we modify PopSyCLE to include a dark matter halo consisting of PBHs. We detail our PBH population model, and demonstrate our PopSyCLE + PBH results through simulations of the OGLE-IV and Roman microlensing surveys. We provide a proof-of-concept analysis for adding PBHs into PopSyCLE, and thus include many simplifying assumptions, such as $f_{\text{DM}}$, the fraction of dark matter composed of PBHs, and $\bar{m}_{\text{PBH}}$, mean PBH mass. Assuming $\bar{m}_{\text{PBH}}=30$ $M_{\odot}$, we find $\sim$ 3.65$f_{\text{DM}}$ times as many PBH microlensing events than stellar evolved black hole events, a PBH average peak Einstein crossing time of $\sim$ 91.4 days, estimate on order of $10^2f_{\text{DM}}$ PBH events within the 8 year OGLE-IV results, and estimate Roman to detect on the order of $10^3f_{\text{DM}}$ PBH microlensing events throughout its planned microlensing survey

Network information and connected correlations

Entropy and information provide natural measures of correlation among elements in a network. We construct here the information theoretic analog of connected correlation functions: irreducible $N$--point correlation is measured by a decrease in entropy for the joint distribution of $N$ variables relative to the maximum entropy allowed by all the observed $N-1$ variable distributions. We calculate the ``connected information'' terms for several examples, and show that it also enables the decomposition of the information that is carried by a population of elements about an outside source.Comment: 4 pages, 3 figure

Increased proportion of active soil N in Breton loam under cropping systems with forages and green manures

Total soil N and N mineralization rate partially ctririct&iie the influence olvariouJcropping systems on the growth of.sequent.crop.s in a rotation' The objectives of this study were to (1) quantify the relationship among cropping system, total N and mineralizable N, and (2) compare amount of N mineralized under'controlled laboratory conditions-with pianl N uptake under green]ouse conditi:ns. Three cropping systems that have been in operation between 9 and 60 yr on a Gray-Luvisol (Breton loam; were ^selected . They included: (1) an ag.lo: ecological (lnn) d-yr rotation involving fabibeans as gr-een manure (AER1 sampled after the_first lababean crop-?nq AER? ,u-pied after 3 yr of continuous forage)l (2) continuous grain system (CG), with fertilizer N at 90 kg ha-'^yr- '; inttrated in 1980 and considered established in f"98i; i3) a classicial Ereton iotation (CBR) involving 9]o-ng-term (ca. 1930) 5-yr rotation with forages and cereals and no return of.ciop residues (CBR1 fertilized with P-K-S and CBR2 unfertilized). We cautio_n that not all ohlses of each rotation were sampled: bur conclusions pertain to N-mineralization potential in soil samples immediately preceding barley as sequent crop in each rotation. The rate ofN mineralization declined with time, but it remained greater than iero aftei 20 wi AER2 > > CBRI > CBR2 : CG. Mineralizable soil N, following one cycle of the AER rotation, was almost double that following 60 yr of the CBR rotation. Data for mineral-N accumulation under laboratory conditions were described best by a single-component expo-n-ential model. Legume-based rotations were associated with increased total soil N and a greater proportional increase in active N than in total soilN. Active N was least in soil under the CG system. The incubation-extraction procedure resulted in higher estimates of mineralizable N than did the plant-uptake method; liowever, the ranking of N-supplying power of soils was the same

Condensation of Injected Electrons and Holes in Germanium

We have demonstrated for the first time that the condensed phase of electrons and holes in germanium can be produced by carrier injection. Germanium devices at liquid-helium temperatures emit intense 708.5-meV recombination radiation characteristic of the condensed phase

The Relation between Black Hole Mass and Host Spheroid Stellar Mass out to z~2

We combine Hubble Space Telescope images from the Great Observatories Origins Deep Survey with archival Very Large Telescope and Keck spectra of a sample of 11 X-ray selected broad-line active galactic nuclei in the redshift range 1<z<2 to study the black hole mass - stellar mass relation out to a lookback time of 10 Gyrs. Stellar masses of the spheroidal component are derived from multi-filter surface photometry. Black hole masses are estimated from the width of the broad MgII emission line and the 3000A nuclear luminosity. Comparing with a uniformly measured local sample and taking into account selection effects, we find evolution in the form M_BH/M_spheroid ~ (1+z)^(1.96+/-0.55), in agreement with our earlier studies based on spheroid luminosity. However, this result is more accurate because it does not require a correction for luminosity evolution and therefore avoids the related and dominant systematic uncertainty. We also measure total stellar masses. Combining our sample with data from the literature, we find M_BH/M_host ~ (1+z)^(1.15+/-0.15), consistent with the hypothesis that black holes (in the range M_BH ~ 10^8-9 M_sun) predate the formation of their host galaxies. Roughly one third of our objects reside in spiral galaxies; none of the host galaxies reveal signs of interaction or major merger activity. Combined with the slower evolution in host stellar masses compared to spheroid stellar masses, our results indicate that secular evolution or minor mergers play a non-negligible role in growing both BHs and spheroids.Comment: 7 pages, 3 figures. Final version, accepted for publication in The Astrophysical Journa

Tuning of Human Modulation Filters Is Carrier-Frequency Dependent

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