Magnetic Field Geometry in "Red" and "Blue" BL Lacs

We compare the systematics of the magnetic field geometry in the "red" low-energy peaked BL Lacs (LBLs) and "blue" high-energy peaked BL Lacs (HBLs) using VLBI polarimetric images. The LBLs are primarily "radio--selected" BL Lacs and the HBLs are primarily "X-ray selected". In contrast to the LBLs, which show predominantly transverse jet magnetic fields, the HBLs show predominantly longitudinal fields. Thus, while the SED peaks of core-dominated quasars, LBLs and HBLs form a sequence of increasing frequency, the magnetic field geometry does not follow an analogous sequence. We briefly investigate possible connections between the observed parsec-scale magnetic field structures and circular polarization measurements in the literature on various spatial scales.Comment: 12 pages, 5 figures, Proceedings of the Amsterdam workshop on "Circular polarisation from relativistic jet sources", to be published in Astrophysics and Space Science, eds. Rob Fender & J-P Macquar

Quasar x-ray spectra revisited

A sample of 45 quasars observed by the Imaging Proportional Counter (IPC) on the Einstein satellite is used to re-examine the relationship between the soft (0.2-3.5 keV) X-ray energy index and radio-loudness. We found the following: (1) the tendency for radio-loud quasars to have systematically flatter X-ray slopes than radio-quiet quasars (RQQ's) is confirmed with the soft X-ray excess having negligible effect; (2) there is a tendency for the flatness of the X-ray slope to correlate with radio core-dominance for radio-loud quasars, suggesting that a component of the X-ray emission is relativistically beamed; (3) for the RQQ's the soft X-ray slopes, with a mean of approximately 1.0, are consistent with the slopes found at higher energies (2-10 keV) although steeper than those observed for Seyfert 1 galaxies (also 2-10 keV) where the reflection model gives a good fit to the data; (4) the correlation of FeII emission line strength with X-ray energy index is confirmed for radio-quiet quasars using a subset of 18 quasars. The radio-loud quasars show no evidence for a correlation. This relation suggests a connection between the ionizing continuum and the line emission from the broad emission line region (BELR) of radio-quiet quasars, but in the opposite sense to that predicted by current photoionization models; and (5) the correlations of X-ray slope with radio core dominance and FeII equivalent width within the radio-loud and radio-quiet sub-classes respectively imply that the observed wide range of X-ray spectral slopes is real rather than due to the large measuring uncertainties for individual objects

Multi-wavelength Observations of the Giant X-ray Flare Galaxy NGC 5905: signatures of tidal disruption

NGC 5905 is one of the few galaxies with no prior evidence for an AGN in which an X-ray flare, due to the tidal disruption of a star by the massive black hole in the center of the galaxy, was detected by the RASS in 1990-91. Here we present analysis of late-time follow-up observations of NGC 5905 using Chandra, Spitzer VLA 3 GHz and 8 GHz archival data and GMRT 1.28 GHz radio observations. The X-ray image shows no compact source that could be associated with an AGN. Instead, the emission is extended -- likely due to nuclear star formation and the total measured X-ray luminosity is comparable to the X-ray luminosity determined from the 2002 Chandra observations. Diffuse X-ray emission was detected close to the circum-nuclear star forming ring. The Spitzer 2006 mid-infrared spectrum also shows strong evidence of nuclear star formation but no clear AGN signatures. The semi-analytical models of Tommasin et. al. 2010 together with the measured [OIV]/[NeII] line ratio suggest that at most only 5.6% of the total IR Flux at 19 $\mu$m is being contributed by the AGN. The GMRT 1.28 GHz observations reveal a nuclear source. In the much higher resolution VLA 3 GHz map, the emission has a double lobed structure of size 2.7'' due to the circumnuclear star forming ring. The GMRT 1.28 GHz peak emission coincides with the center of the circumnuclear ring. We did not detect any emission in the VLA 8 GHz (1996) archival data. The 3 $\sigma$ upper limits for the radio afterglow of the TDE at 1.28 GHz, 3 GHz and 8 GHz are 0.17 mJy, 0.09 mJy and 0.09 mJy, respectively. Our studies thus show that (i) NGC 5905 has a declining X-ray flux consistent with a TDE, (ii) the IR flux is dominated by nuclear star formation, (iii) the nuclear radio emission observed from the galaxy is due to circumnuclear star formation, (iv) no compact radio emission associated with a radio afterglow from the TDE is detected.Comment: 12 pages, 8 figures, accepted to be published in Astrophysics and Space Scienc

Material Internal Control Weaknesses And Earnings Management In The Post-SOX Environment

Prior studies found that companies with internal control deficiencies incorporate abnormal accounting accruals into their financial statements. However, these studies did not consider the materiality of abnormal accruals. Abnormal accruals should be within materiality when financial statements receive clean audit opinions. When material internal control weaknesses (MICW) exist, to compensate for additional risk, auditors should apply more audit effort to gain the quantity and quality of evidence necessary to obtain a reasonable degree of assurance to support their audit reports. We find evidence of this because audit fees are significantly higher for MICW companies than those for effective internal controls (EIC) companies in our sample. Accordingly, financial statements receiving clean audit opinions should not contain material abnormal accruals irrespective of whether controls are effective EIC or ineffective MICW. To examine this issue, we use post-SOX data to estimate abnormal accruals using a revenue-based accrual model for a matched sample of companies with clean audit opinions on their financial statements: one-half EIC and the other half with MICW. Then, we establish material abnormal revenue accruals (MARA), which is the difference between estimated abnormal revenue accruals and a quantitative materiality based on assets. Finally, we compare MARA between EIC and MICW companies. We find no significant difference in MARA between EIC and MICW companies. We provide a summary of important findings in Table 3, and conclude with suggestions to further improve audit and financial reporting quality

Material Internal Control Weaknesses And Earnings Management In The Post-SOX Environment

Prior studies found that companies with internal control deficiencies incorporate abnormal accounting accruals into their financial statements. However, these studies did not consider the materiality of abnormal accruals. Abnormal accruals should be within materiality when financial statements receive clean audit opinions. When material internal control weaknesses (MICW) exist, to compensate for additional risk, auditors should apply more audit effort to gain the quantity and quality of evidence necessary to obtain a reasonable degree of assurance to support their audit reports. We find evidence of this because audit fees are significantly higher for MICW companies than those for effective internal controls (EIC) companies in our sample. Accordingly, financial statements receiving clean audit opinions should not contain material abnormal accruals irrespective of whether controls are effective EIC or ineffective MICW. To examine this issue, we use post-SOX data to estimate abnormal accruals using a revenue-based accrual model for a matched sample of companies with clean audit opinions on their financial statements: one-half EIC and the other half with MICW. Then, we establish material abnormal revenue accruals (MARA), which is the difference between estimated abnormal revenue accruals and a quantitative materiality based on assets. Finally, we compare MARA between EIC and MICW companies. We find no significant difference in MARA between EIC and MICW companies. We provide a summary of important findings in Table 3, and conclude with suggestions to further improve audit and financial reporting quality

Mentoring, Career Plateau Tendencies, Turnover Intentions And Implications For Narrowing Pay And Position Gaps Due To Gender Structural Equations Modeling

This study analyzed responses to career-related questions from a survey of experienced Canadian Certified Management Accountants (CMAs), relative experts in the field of management accounting, to address how mentoring affects turnover intentions and career plateau tendency of male and female accounting professionals in industry. In this regard, we used structural equations modeling to build and test a framework illustrating the impact of mentoring and career-related factors. Results indicate that fostering a mentoring environment within an organization can strengthen CMAs perceptions of their careers and employers. Mentoring has also been suggested to enhance womens opportunities to advance in organizations and help women break the glass ceiling. Analyses of data relating to compensation in 2007 and 2009 for a sample of female and male CEOs and operating performance of companies led by these CEOs for these years indicate that, that compensation gaps due to gender appear to be narrowing at the top management level

The Impact Of Mentoring On Career Plateau And Turnover Intentions Of Management Accountants

The presence of frustrated employees in an organization is likely to have a significant adverse effect on the organization’s operations. Employees faced with a career plateau are likely to exhibit feelings of frustration. Such employees may have a higher tendency to leave the company, increasing employee turnover.  Using Canadian Certified Management Accountants (CMAs), as subjects, this study examined the effect of mentoring on employee career plateau tendencies and turnover intentions.  Survey questionnaires were mailed and responses obtained from 235 CMAs.  Subjects’ responses were factor analyzed to develop composite scales about CMAs’ perceptions for mentoring (MENTOR), career plateau (PLAT), turnover intentions (EXIT), positive job attributes (PJA), and job satisfaction rate (JSR).   For hypotheses testing, the means of the scaled values were used in statistical tests of relationships between the measures. Tests indicated that mentoring reduces plateau tendency significantly and significantly lowers turnover intentions even after controlling for career plateau, job satisfaction, and positive job attributes. The results imply that fostering a mentoring environment can reduce career plateau attainment and turnover intentions. Reducing career plateau in turn is likely to have positive impact on organization’s operations. For example, CMAs are often involved in, among other matters, the operational information and financial reporting process.  Therefore, reducing CMAs’ career plateau tendencies and turnover intentions could improve the quality of an organization’s financial reporting process

Mentoring, Career Plateau Tendencies, Turnover Intentions And Implications For Narrowing Pay And Position Gaps Due To Gender Structural Equations Modeling

This study analyzed responses to career-related questions from a survey of experienced Canadian Certified Management Accountants (CMAs), relative experts in the field of management accounting, to address how mentoring affects turnover intentions and career plateau tendency of male and female accounting professionals in industry. In this regard, we used structural equations modeling to build and test a framework illustrating the impact of mentoring and career-related factors. Results indicate that fostering a mentoring environment within an organization can strengthen CMAs perceptions of their careers and employers. Mentoring has also been suggested to enhance womens opportunities to advance in organizations and help women break the glass ceiling. Analyses of data relating to compensation in 2007 and 2009 for a sample of female and male CEOs and operating performance of companies led by these CEOs for these years indicate that, that compensation gaps due to gender appear to be narrowing at the top management level

A Polarization Study of 3 Blazars using the uGMRT at ~600 MHz

We present results from our radio polarimetric study with the upgraded Giant Metrewave Radio Telescope (uGMRT) at Band 4 (550-850 MHz) of 3 blazars: radio-loud quasars 3C390.3, 4C71.07 and BL Lac object 1ES 2344+514. The aim of this study was (i) to carry out a feasibility study for Band 4 polarization with the uGMRT, and (ii) to compare and contrast the kpc-scale polarization properties between the blazar sub-classes. We have detected linear polarization in all the three sources. The degree of linear polarization in the cores of the two quasars is higher than in the BL Lac object, consistent with similar differences observed on parsec-scales in blazars. The highest fractional polarization of 15% is observed in the hotspot region of 3C390.3, which also shows extended polarized lobe structures. 1ES 2344+514 shows a core-halo structure whereas 4C71.07 remains unresolved. A rotation of polarization electric vectors along the northern hotspot of 3C390.3, and the core of 1ES 2344+514, suggest jet bending. Greater depolarization in the southern lobe of 3C390.3 compared to the northern lobe indicates the presence of the `Laing-Garrington effect'. Multi-frequency uGMRT polarimetric data are underway to study the kpc-scale rotation measures across these sources in order to look for differences in the surrounding media.Comment: 13 pages, 6 figures, accepted by Journal of Astrophysics and Astronom