Recoiling Supermassive Black Holes: a search in the Nearby Universe

The coalescence of a binary black hole can be accompanied by a large gravitational recoil due to anisotropic emission of gravitational waves. A recoiling supermassive black hole (SBH) can subsequently undergo long-lived oscillations in the potential well of its host galaxy, suggesting that offset SBHs may be common in the cores of massive ellipticals. We have analyzed HST archival images of 14 nearby core ellipticals, finding evidence for small ($\lesssim 10$ pc) displacements between the AGN (locating the SBH) and the center of the galaxy (the mean photocenter) in 10 of them. Excluding objects that may be affected by large-scale isophotal asymmetries, we consider six galaxies to have detected displacements, including M87, where a displacement was previously reported by Batcheldor et al. 2010. In individual objects, these displacements can be attributed to residual gravitational recoil oscillations following a major or minor merger within the last few Gyr. For plausible merger rates, however, there is a high probability of larger displacements than those observed, if SBH coalescence took place in these galaxies. Remarkably, the AGN-photocenter displacements are approximately aligned with the radio source axis in four of the six galaxies with displacements, including three of the four having relatively powerful kpc-scale jets. This suggests intrinsic asymmetries in radio jet power as a possible displacement mechanism, although approximate alignments are also expected for gravitational recoil. Orbital motion in SBH binaries and interactions with massive perturbers can produce the observed displacement amplitudes but do not offer a ready explanation for the alignments.Comment: 58 pages, 32 figures, 9 tables. Accepted for publication in Ap

A Complete Characterization of Irreducible Cyclic Orbit Codes and their Pl\"ucker Embedding

Constant dimension codes are subsets of the finite Grassmann variety. The study of these codes is a central topic in random linear network coding theory. Orbit codes represent a subclass of constant dimension codes. They are defined as orbits of a subgroup of the general linear group on the Grassmannian. This paper gives a complete characterization of orbit codes that are generated by an irreducible cyclic group, i.e. a group having one generator that has no non-trivial invariant subspace. We show how some of the basic properties of these codes, the cardinality and the minimum distance, can be derived using the isomorphism of the vector space and the extension field. Furthermore, we investigate the Pl\"ucker embedding of these codes and show how the orbit structure is preserved in the embedding.Comment: submitted to Designs, Codes and Cryptograph

Pengaruh Kebijakan Dividen, Kebijakan Hutang, dan Keputusan Investasi terhadap Nilai Perusahaan pada Sub Sektor Perdagangan Besar yang Terdaftar di Bursa Efek Indonesia Periode 2010-2014

This study aimed to determine the effect of dividend policy, debt policy and investment decisions of the Company value in the Sub Sector wholesale listed in Indonesia Stock Exchange study period of 2010 - 2014. The independent variables Dividend Policy are the indicators dividend Payout Ratio (DPR), Debts policy with indicators Debt to Equity Ratio (DER), and Investment Decisions with indicators of Price Earning Ratio (PER). While that is used as the dependent variable is the value the company at indikatorkan Price to Book Value (PBV). The method used to observe the effect of Dividend Policy, Debt Policy and Investment Decisions to the company Value is using multiple linear regression.This study uses secondary data from financial statements of companies. Samples and sampling using purposive sampling techniques. Classic assumption test in this study include normality test, multicollinearity test, heterocedasticity test and autocorrelation test. Analysis of data using multiple linear regression analysis, t test, F test, and test the coefficient of determination. Analysis of data using multiple linear regression analysis with SPSS 16.The results showed that the variables DPR and DER partially (t test) did not significant effect on the PBV on wholesale sub sector listed on the Indonesia Stock Exchange, while the variable PER significant effect on the PBV on wholesale sub sector listed in Indonesia Stock Exchange. The results of simultaneous (f test) showed a significant effect of the variable DPR, DER, and PER to PBV on the wholesale sub sector registered in the Indonesia Stock Exchange

Pengaruh Ratio Profitabilitas Terhadap Harga Saham Pada Bank Milik Pemerintah ( Bumn ) Yang Terdaftar Di Bursa Efek Indonesia ( Bei ) Periode 2007-2014

This reasearch aimed to analyze the influence of the profitability ratio on stock prices at state-owned bank (BUMN) listed on the Indonesia Stock Exchange (BEI) in the period of 2007-2014. This research used financial ratio analysis, it was profitability ratio which was analyzed by using the variables of profitability itself, they were : Return on Assets (ROA) Return on Equity (ROE), Net Profit Margin (NPM), and Earnings per Share (EPS). The method used to observe the effect of the profitability ratio on stock prices was simple linear regression of statistical analysis. The results of this research indicate that ROA does not have a significant effect on stock prices, and variabel of ROE, NPM, EPS have a significant effect on stock prices.Keywords : Profitability Ratio, Stock Prices, ROA, ROE, NPM, EP

Pengaruh Retrun on Invesment (Roi) Dan Price Earning Ratio Terhadap Harga Saham Pada Perusahaan Makanan Dan Minuman Yang Terdaftar Bi Bursa Efek Indonesia Bei Pada Periode 2011- 2014

In examining the effect of return on investment as (ROI) and price earnings ratio (PER) on stock prices on food and beverage companies listed on the Stock Exchange will be used by several variables: the first is Return On Investment (ROI) that is how many the ability of the company's overall generating profits in the aggregate assets tersedian within the company, it is for investors to see how far the company's ability to manage their own capital to generate net income. The second is the price earnings ratio (PER) provides an overview of the company's ability to determine the price of shares. In this study aims to test whether the effect of the Return on investmean (ROI) Dan Price earning ratio (PER) on stock prices on food and beverage companies that have been listed in the Indonesia Stock Exchange (BEI) by taking a sample of 4 year study period, namely in 2011- 2014. Samples were used as research material there are five companies of drinks and food are equally listed since 1994 on the Indonesian Stock Exchange (BEI) although this study only in grab samples but is expected to serve as a reference and a general description of one of the companies that have been listed in ( BEI). Data analysis technique used is multiple linear regression and hypothesis testing using t test. And f test the conclusions of this study are variable ROI have a significant effect on stock prices and PER variables influence the stock price, to test the effect of ROI, PER and stock prices with SPSS memggunakan formul

Broad application of a simple and affordable protocol for isolating plant RNA

BACKGROUND: Standard molecular biological methods involve the analysis of gene expression in living organisms under diverse environmental and developmental conditions. One of the most direct approaches to quantify gene expression is the isolation of RNA. Most techniques used to quantify gene expression require the isolation of RNA, usually from a large number of samples. While most published protocols, including those for commercial reagents, are either labour intensive, use hazardous chemicals and/or are costly, a previously published protocol for RNA isolation in Arabidopsis thaliana yields high amounts of good quality RNA in a simple, safe and inexpensive manner. FINDINGS: We have tested this protocol in tomato and wheat leaves, as well as in Arabidopsis leaves, and compared the resulting RNA to that obtained using a commercial phenol-based reagent. Our results demonstrate that this protocol is applicable to other plant species, including monocots, and offers yield and purity at least comparable to those provided by commercial phenol-based reagents. CONCLUSIONS: Here, we show that this previously published RNA isolation protocol can be easily extended to other plant species without further modification. Due to its simplicity and the use of inexpensive reagents, this protocol is accessible and affordable and can be easily implemented to work on different plant species in laboratories worldwide

Characterisation of a candidate dual AGN

We present Chandra and optical observations of a candidate dual AGN discovered serendipitously while searching for recoiling black holes via a cross-correlation between the serendipitous XMM source catalog (2XMMi) and SDSS-DR7 galaxies with a separation no larger than ten times the sum of their Petrosian radii. The system has a stellar mass ratio M$_{1}$/M$_{2}\approx 0.7$. One of the galaxies (Source 1) shows clear evidence for AGN activity in the form of hard X-ray emission and optical emission-line diagnostics typical of AGN ionisation. The nucleus of the other galaxy (Source 2) has a soft X-ray spectrum, bluer colours, and optical emission line ratios dominated by stellar photoionisation with a "composite" signature, which might indicate the presence of a weak AGN. When plotted on a diagram with X-ray luminosity vs [OIII] luminosity both nuclei fall within the locus defined by local Seyfert galaxies. From the optical spectrum we estimate the electron densities finding n$_{1} < 27$ e$^{-}$ cm$^{-3}$ and n$_{2} \approx 200$ e$^{-}$ cm$^{-3}$. From a 2D decomposition of the surface brightness distribution we infer that both galaxies host rotationally supported bulges (Sersic index $< 1$). While the active nature of Source 1 can be established with confidence, whether the nucleus of Source 2 is active remains a matter of debate. Evidence that a faint AGN might reside in its nucleus is, however, tantalising.Comment: 16 pages, 9 figures. Accepted for publication on MNRAS. Comments welcom

Windows into Non-Euclidean Spaces

Two microlens arrays that are separated by the sum of their focal lengths form arrays of micro-telescopes. Parallel light rays that pass through corresponding lenses remain parallel, but the direction of the transmitted light rays is different. This remains true if corresponding lenses do not share an optical axis (i.e. if the two microlens arrays are shifted with respect to each other). The arrays described above are examples of generalized confocal lenslet arrays, and the light-ray-direction change in these devices is well understood [Oxburgh et al., Opt. Commun. 313, 119 (2014)]. Here we show that such micro-telescope arrays change light-ray direction like the interface between spaces with different metrics. To physicists, the concept of metrics is perhaps most familiar from General Relativity (where it is applied to spacetime, not only space, like it is here) and Transformation Optics [Pendry et al., Science 312, 1780 (2006)], where different materials are treated like spaces with different optical metrics. We illustrate the similarities between micro-telescope arrays and metric interfaces with raytracing simulations. Our results suggest the possibility of realising transformation-optics devices with micro-telescope arrays, which we investigate elsewhere