We present reverberation mapping results from the first year of combined spectroscopic and photometric observations of the Sloan Digital Sky Survey Reverberation Mapping Project. We successfully recover reverberation time delays between the g+i band emission and the broad Hβ emission line for a total of 44 quasars, and for the broad Hα emission line in 18 quasars. Time delays are computed using the JAVELIN and CREAM software and the traditional interpolated cross-correlation function (ICCF): using well-defined criteria, we report measurements of 32 Hβ and 13 Hα lags with JAVELIN, 42 Hβ and 17 Hα lags with CREAM, and 16 Hβ and eight Hα lags with the ICCF. Lag values are generally consistent among the three methods, though we typically measure smaller uncertainties with JAVELIN and CREAM than with the ICCF, given the more physically motivated light curve interpolation and more robust statistical modeling of the former two methods. The median redshift of our Hβ-detected sample of quasars is 0.53, significantly higher than that of the previous reverberation mapping sample. We find that in most objects, the time delay of the Hα emission is consistent with or slightly longer than that of Hβ. We measure black hole masses using our measured time delays and line widths for these quasars. These black hole mass measurements are mostly consistent with expectations based on the local M BH -* s relationship, and are also consistent with single-epoch black hole mass measurements. This work increases the current sample size of reverberation-mapped active galaxies by about two-thirds and represents the first large sample of reverberation mapping observations beyond the local universe (z<0.3).

We present host stellar velocity dispersion measurements for a sample of 88 broad-line quasars at 0.1 < z < 1 (46 at z > 0.6) from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. High signalto-noise ratio coadded spectra (average S/N ≈ 30 per 69 km s −1 pixel) from SDSS-RM allowed decomposition of the host and quasar spectra, and measurements of the host stellar velocity dispersions and black hole (BH) masses using the single-epoch (SE) virial method. The large sample size and dynamic range in luminosity (L 5100 = 10 43.2−44.7 erg s −1 ) lead to the first clear detection of a correlation between SE virial BH mass and host stellar velocity dispersion far beyond the local universe. However, the observed correlation is significantly flatter than the local relation, suggesting that there are selection biases in high-z luminosity-threshold quasar samples for such studies. Our uniform sample and analysis enable an investigation of the redshift evolution of the M • − σ * relation relatively free of caveats by comparing different samples/analyses at disjoint redshifts. We do not observe evolution of the M • − σ * relation in our sample up to z ∼ 1, but there is an indication that the relation flattens towards higher redshifts. Coupled with the increasing threshold luminosity with redshift in our sample, this again suggests certain selection biases are at work, and simple simulations demonstrate that a constant M • − σ * relation is favored to z ∼ 1. Our results highlight the scientific potential of deep coadded spectroscopy from quasar monitoring programs, and offer a new path to probe the co-evolution of BHs and galaxies at earlier times.

Axions and axion-like particles (ALPs) are a well motivated extension of the Standard Model and are generic in String Theory. The X-ray transparency of the magnetized intracluster medium (ICM) in galaxy clusters is a powerful probe of very light ALPs (masses 0 < m a < 10 −11 eV); as X-ray photons propagate through the magnetic field of the ICM, they may undergo energy-dependent quantum mechanical conversion into ALPs (and vice versa), imprinting distortions on the observed X-ray spectrum. We present new Chandra data for the active galactic nucleus NGC 1275 at the center of the Perseus cluster. Employing the High-Energy Transmission Gratings (HETG) with a 490 ks exposure, we obtain a high-quality 1-9 keV spectrum free from photon pileup and ICM contamination. Apart from iron-band features, the spectrum is accurately described by a power-law continuum, with any spectral distortions at the < 3% level. We compute photon survival probabilities as a function of ALP mass m a and ALP-photon coupling constant g aγ for an ensemble of ICM magnetic field models, and then use the NGC 1275 spectrum to derive constraints on the (m a , g aγ )-plane. Marginalizing over the magnetic field realizations, the 99.7% credible region limits the ALP-photon coupling to g aγ < 6 − 8 × 10 −13 GeV −1 (depending upon the magnetic field model) for masses m a < 1 × 10 −12 eV. These are the most stringent limit to date on g aγ for these very light ALPs, and have already reached the sensitivity limits of next-generation helioscopes and light-shining-through-wall experiments. We highlight the potential of these studies with the next-generation X-ray observatories Athena and Lynx, but note the critical importance of advances in relative calibration of these future X-ray spectrometers.

A complex of coalescing ridges and diverse marginal features observed in Mariner 9 pictures of the Hellespontus region of Mars is identified as a dune mass. Many other possible dune features are recognized in mid‐latitudes and polar latitudes, and regional differences in the appearance of cratered terrains are attributed to modification by dune deposits. The morphology and temporal behavior of some Martian albedo features can be explained by dune‐forming saltation processes. Eolian activity seems to be widespread, if not ubiquitous, on Mars and appears to produce major regional variations in the surface environment.

The alkali-metal salts (potassium and sodium) of a large number of aryl-and heteroarylsilanols undergo efficient cross coupling with a wide range of aromatic bromides and chlorides under mild conditions to form polysubstituted biaryls. The critical feature for the success of these coupling reactions and their considerable scope is the use of bis(tri-tert-butylphosphine)palladium. Under the optimized conditions, electron-rich, electron-poor, and sterically hindered arylsilanolates afford cross-coupling products in good yields. Many functional groups are compatible with the coupling conditions such as esters, ketones, acetals, ethers, silyl ethers, and dimethylamino groups. Two particularly challenging substrates, (2-benzofuranyl)dimethylsilanolate and (2,6-dichlorophenyl) dimethylsilanolate prepared as their sodium salts showed excellent activity in the coupling reactions, in the former case also with aromatic chlorides. General methods for the efficient synthesis of a wide range of aromatic silanols are also described.

Acetals are obtained in good yields by treatment of aldehydes and ketones with trialkyl orthoformate and the corresponding alcohol in the presence of 0.1 mol % Bi(OTf)3.4H2O. A simple procedure for the formation of acetals of diaryl ketones has also been developed. The conversion of carbonyl compounds to the corresponding 1,3-dioxolane using ethylene glycol is also catalyzed by Bi(OTf)3.4H2O (1 mol %). Two methods, both of which avoid the use of benzene, have been developed.

Small-ring cage hydrocarbons are common bioisosteres for para-substituted benzene rings in drug design 1 . The popularity of these structures derives from the superior pharmacokinetic properties they exhibit compared to the parent aromatics, including improved solubility and reduced susceptibility to metabolism 2,3 . A prime example is the bicyclo[1.1.1]pentane motif, which is mainly synthesised by ring-opening of the inter-bridgehead bond of the strained hydrocarbon [1.1.1]propellane with radicals or anions 4 . In contrast, scaffolds mimicking metasubstituted arenes are lacking due to the challenge of synthesising saturated isosteres that accurately reproduce substituent vectors 5 . Here we show that bicyclo[3.1.1]heptanes (BCHeps), hydrocarbons whose bridgehead substituents map precisely onto the geometry of meta-substituted benzenes, can be conveniently accessed from [3.1.1]propellane. We found that [3.1.1]propellane can be synthesized on multigram scale, and readily undergoes a range of radical-based transformations to generate medicinally-relevant carbon-and heteroatom-substituted BCHeps, including pharmaceutical

Axion-Like Particles (ALPs) are predicted by several Beyond the Standard Model theories, in particular, string theory. In the presence of an external magnetic field perpendicular to the direction of propagation, ALPs can couple to photons. Therefore, if an X-ray source is viewed through a magnetised plasma, such as a luminous quasar in a galaxy cluster, we may expect spectral distortions that are well described by photon-ALP oscillations. We present a 571 ks combined High and Low Energy Transmission Grating (HETG/LETG) Chandra observation of the powerful radio-quiet quasar H1821+643, hosted by a cool-core cluster at redshift 0.3. The spectrum is well described by a double power-law continuum and broad+narrow iron line emission typical of type-1 Active Galactic Nuclei (AGN), with remaining spectral features $&lt; 2.5\%$. Using a cell-based approach to describe the turbulent cluster magnetic field, we compare our spectrum with photon-ALP mixing curves for 500 field realisations, assuming that the thermal-to-magnetic pressure ratio β remains constant up to the virial radius. At $99.7\%$ credibility and taking β = 100, we exclude all couplings gaγ &gt; 6.3 × 10−13 GeV−1 for most ALP masses &lt;10−12 eV. Our results are moderately more sensitive to constraining ALPs than the best previous result from Chandra observations of the Perseus cluster, albeit with a less constrained field model. We reflect on the promising future of ALP studies with bright AGN embedded in rich clusters, especially with the upcoming Athena mission.