Supermassive Black Hole Mass Estimates Using Sloan Digital Sky Survey Quasar Spectra at 0.7 < z < 2

We present MgII-based black hole mass estimates for 27,602 quasars with rest-frame UV spectra available in the Sloan Digital Sky Survey Data Release Three. This estimation is possible due to the existence of an empirical correlation between the radius of the broad line region and the continuum luminosity at 3000 Angstroms. We regenerate this correlation by applying our measurement method to UV spectra of low-redshift quasars in the HST/IUE databases which have corresponding reverberation mapping estimates of the Hbeta broad line region's radius. Our mass estimation method uses the line dispersion rather than the full width at half maximum of the low-ionization MgII emission line. We measure MgII line dispersions for quasars whose spectra have been reconstructed using the most significant eigenspectra produced through Principal Component Analysis. We have tested the reliability of using reconstructed spectra in black hole mass estimation using a Monte Carlo simulation and by comparing the results from original and reconstructed Data Release Three spectra. We show that using reconstructed spectra not only makes bias-free mass estimation possible for quasars with low spectroscopic signal-to-noise ratio, but also reduces the intrinsic scatter of the distribution of the black hole masses to lower than 0.15 dex.Comment: 38 Pages, 12 figures, 3 Tables, 1 hyperlink to catalogue data. Accepted for publication in ApJ

The Ensemble Photometric Variability of ~25000 Quasars in the Sloan Digital Sky Survey

Using a sample of over 25000 spectroscopically confirmed quasars from the Sloan Digital Sky Survey, we show how quasar variability in the rest frame optical/UV regime depends upon rest frame time lag, luminosity, rest wavelength, redshift, the presence of radio and X-ray emission, and the presence of broad absorption line systems. The time dependence of variability (the structure function) is well-fit by a single power law on timescales from days to years. There is an anti-correlation of variability amplitude with rest wavelength, and quasars are systematically bluer when brighter at all redshifts. There is a strong anti-correlation of variability with quasar luminosity. There is also a significant positive correlation of variability amplitude with redshift, indicating evolution of the quasar population or the variability mechanism. We parameterize all of these relationships. Quasars with RASS X-ray detections are significantly more variable (at optical/UV wavelengths) than those without, and radio loud quasars are marginally more variable than their radio weak counterparts. We find no significant difference in the variability of quasars with and without broad absorption line troughs. Models involving multiple discrete events or gravitational microlensing are unlikely by themselves to account for the data. So-called accretion disk instability models are promising, but more quantitative predictions are needed.Comment: 41 pages, 21 figures, AASTeX, Accepted for publication in Ap

Parents ice-hockey habitus and their childrens' participation

Rooted and centered within a Bourdieu-inspired understanding of how the habitus and social class of parents affects childrens’ sports choices, this paper contributes to a greater appreciation of how social capital and social background impact a family’s ability to practice the sport of ice-hockey. Historically, there has been a significant amount of research investigating the reasons for- and rates of- dropout from sports participation, but few attempts has been undertaken to study athletes who begin and continue to actively play a certain sport. Through the creation of an index which measures different variables, this paper introduces the concept of an ice-hockey habitus. This habitus was used to compare the education, occupations, economic wealth and other demographic parameters of parents of ice-hockey-playing children. With that in mind, the aim of this paper was to investigate what characterizes ice-hockey playing childrens’ parents. The results were found through looking at the above-mentioned demographics in relation to previous research, and, briefly, the UN Convention on the Rights of the Child. Additionally, a further aim is to document the demographics of the parents of continual-participation among young ice-hockey players. To do so, a quantitative research method was utilized, through which a web-based questionnaire was formed and used as foundation for the gathering of the empirical data. The total amount of responses amounted to n=576, from four disparate cities within a geographical distribution from south to north. The findings showed that there was a correlation between families with ice-hockey playing children and highly educated parents (in some areas more than double the Swedish average) and economic wealth (as more than four out of five families earns equal to- or higher than the Swedish average). The findings also showed that for the ice-hockey habitus, level of education did not affect mothers’ index level. For the fathers’ index, the amount of highly educated fathers decreased as the ice-hockey habitus increased. A further correlation found was that as ice-hockey habitus increased, so did the amount of families with higher economic wealth

Parents ice-hockey habitus and their childrens' participation

Rooted and centered within a Bourdieu-inspired understanding of how the habitus and social class of parents affects childrens’ sports choices, this paper contributes to a greater appreciation of how social capital and social background impact a family’s ability to practice the sport of ice-hockey. Historically, there has been a significant amount of research investigating the reasons for- and rates of- dropout from sports participation, but few attempts has been undertaken to study athletes who begin and continue to actively play a certain sport. Through the creation of an index which measures different variables, this paper introduces the concept of an ice-hockey habitus. This habitus was used to compare the education, occupations, economic wealth and other demographic parameters of parents of ice-hockey-playing children. With that in mind, the aim of this paper was to investigate what characterizes ice-hockey playing childrens’ parents. The results were found through looking at the above-mentioned demographics in relation to previous research, and, briefly, the UN Convention on the Rights of the Child. Additionally, a further aim is to document the demographics of the parents of continual-participation among young ice-hockey players. To do so, a quantitative research method was utilized, through which a web-based questionnaire was formed and used as foundation for the gathering of the empirical data. The total amount of responses amounted to n=576, from four disparate cities within a geographical distribution from south to north. The findings showed that there was a correlation between families with ice-hockey playing children and highly educated parents (in some areas more than double the Swedish average) and economic wealth (as more than four out of five families earns equal to- or higher than the Swedish average). The findings also showed that for the ice-hockey habitus, level of education did not affect mothers’ index level. For the fathers’ index, the amount of highly educated fathers decreased as the ice-hockey habitus increased. A further correlation found was that as ice-hockey habitus increased, so did the amount of families with higher economic wealth

Parents ice-hockey habitus and their childrens' participation

Rooted and centered within a Bourdieu-inspired understanding of how the habitus and social class of parents affects childrens’ sports choices, this paper contributes to a greater appreciation of how social capital and social background impact a family’s ability to practice the sport of ice-hockey. Historically, there has been a significant amount of research investigating the reasons for- and rates of- dropout from sports participation, but few attempts has been undertaken to study athletes who begin and continue to actively play a certain sport. Through the creation of an index which measures different variables, this paper introduces the concept of an ice-hockey habitus. This habitus was used to compare the education, occupations, economic wealth and other demographic parameters of parents of ice-hockey-playing children. With that in mind, the aim of this paper was to investigate what characterizes ice-hockey playing childrens’ parents. The results were found through looking at the above-mentioned demographics in relation to previous research, and, briefly, the UN Convention on the Rights of the Child. Additionally, a further aim is to document the demographics of the parents of continual-participation among young ice-hockey players. To do so, a quantitative research method was utilized, through which a web-based questionnaire was formed and used as foundation for the gathering of the empirical data. The total amount of responses amounted to n=576, from four disparate cities within a geographical distribution from south to north. The findings showed that there was a correlation between families with ice-hockey playing children and highly educated parents (in some areas more than double the Swedish average) and economic wealth (as more than four out of five families earns equal to- or higher than the Swedish average). The findings also showed that for the ice-hockey habitus, level of education did not affect mothers’ index level. For the fathers’ index, the amount of highly educated fathers decreased as the ice-hockey habitus increased. A further correlation found was that as ice-hockey habitus increased, so did the amount of families with higher economic wealth