Galaxy gas ejection in radio galaxies: the case of 3C 35

We report results from XMM-Newton and Chandra observations of the nearby (z = 0.067) giant radio galaxy 3C 35. We find evidence for an X-ray emitting gas belt, orthogonal to and lying between the lobes of 3C 35, which we interpret as fossil-group gas driven outwards by the expanding radio lobes. We also detect weak emission from a second, more extended group-type environment, as well as inverse-Compton X-ray emission from the radio lobes. The morphological structure of the radio lobes and gas belt point to co-evolution. Furthermore, the radio source is powerful enough to eject galaxy-scale gas out to distances of 100kpc, and the ages of the two features are comparable (tsynch~140Myr, tbelt~80 Myr). The destruction of 3C 35's atmosphere may offer clues as to how fossil systems are regulated: radio galaxies need to be of power comparable to 3C 35 to displace and regulate fossil-group gas. We discuss the implications of the gas belt in 3C 35 in terms of AGN fuelling and feedback.Comment: 18 pages, accepted to MNRA

Identifying clustering at high redshift through actively star-forming galaxies

Identifying galaxy clustering at high redshift (i.e. z > 1) is essential to our understanding of the current cosmological model. However, at increasing redshift, clusters evolve considerably in star-formation activity and so are less likely to be identified using the widely-used red sequence method. Here we assess the viability of instead identifying high redshift clustering using actively star-forming galaxies (SMGs associated with over-densities of BzKs/LBGs). We perform both a 2- and 3-D clustering analysis to determine whether or not true (3D) clustering can be identified where only 2D data are available. As expected, we find that 2D clustering signals are weak at best and inferred results are method dependant. In our 3D analysis, we identify 12 SMGs associated with an over-density of galaxies coincident both spatially and in redshift - just 8% of SMGs with known redshifts in our sample. Where an SMG in our target fields lacks a known redshift, their sightline is no more likely to display clustering than blank sky fields; prior redshift information for the SMG is required to identify a true clustering signal. We find that the strength of clustering in the volume around typical SMGs, while identifiable, is not exceptional. However, we identify a small number of highly clustered regions, all associated with an SMG. The most notable of these, surrounding LESSJ033336.8-274401, potentially contains an SMG, a QSO and 36 star-forming galaxies (a > 20sig over-density) all at z~1.8. This region is highly likely to represent an actively star-forming cluster and illustrates the success of using star-forming galaxies to select sites of early clustering. Given the increasing number of deep fields with large volumes of spectroscopy, or high quality and reliable photometric redshifts, this opens a new avenue for cluster identification in the young Universe.Comment: 24 pages, 14 figures, accepted MNRA

Wool Textiles and Archaeometry: Testing Reliability of Archaeological Wool Fibre Diameter

Characterisations of ancient sheep breeds and wool types as well as theories about wool fibre processing have become integral parts of textile archaeology. The studies are based on statistical calculations of measurements of wool fibre diameters and reveal characteristics of the yarns that can be attributed to the available raw wool and to the production methods of the people creating the textiles. The types of microscopes used for the analyses have varied through the years and presently digital images from either scanning electron microscopy (SEM) or transmitted light microscopy (TLM) are the preferred methods for data collection. The advantage of SEM is the good depth of field at high magnification while TLM is simpler to use and more readily available. Several classification systems have been developed to facilitate the interpretation of the results. In this paper the comparability of the results from these two methods and from the use of different magnifications in general is examined based on the analyses of a large number of the Danish prehistoric textiles. The results do not indicate superiority of one microscope type in favour of another. Rather, they reveal differences in the calculations that can be ascribed to the diversity of the fibres in the individual yarns as well as to the methodology and the magnification level.The research leading to these results was funded by the Danish National Research Foundation’s Centre for Textile Research [DNRF64], the National Museum of Denmark, the European Commission’s Marie Curie Actions under the European Union’s Seventh Framework Programme [FP7-PEOPLE-IEF-2008-236263], and the European Research Council under the European Union’s Seventh Framework Programme [FP/2007-2013-312603]

A hazard-based analysis of airport security transit times

AbstractAirport security screening, and the amount of time it costs travelers, has been a persistent concern to travelers, airport authorities, and airlines – particularly in recent years where changes in perceived threats have resulted in changes in security procedures that have caused great uncertainty relating to security transit times. To gain a better understanding of the factors influencing travelers' security transit times, determinants of security transit times are studied by using anonymous Bluetooth media access control address matching to determine the actual security travel times of individual passengers at the Cincinnati/Northern Kentucky International Airport. These transit-time data are then analyzed using a random-parameters hazard-based duration model to statistically explore the factors that affect airport security transit times. The estimation results reveal, as expected, that a wide variety of factors affect security transit times including the number of enplaning seats (reflecting flight schedules), weather conditions, day of week, as well as obvious variables such as traveler volume and the number of open security lanes. The detailed statistical findings show that current security procedures are reactive instead of proactive, and that substantial reductions in security transit times could be attained by optimizing security operations using a statistical model such as the one estimated in this paper

SEX-DEPENDENT DIFFERENCES IN DRUG METABOLISM IN THE RAT III. Temporal Changes in Type I Binding and NADPH-Cytochrome, P-450 Reductase during Sexual Maturation

ABSTRACT Microsomal ethylmorphine N-demethylase activity increased with age in male rats, but decreased with age in female rats. Relative to the cytochrome P-450 content of microsomes

Limits on dust emission from z~5 LBGs and their local environments

We present 1.2mm MAMBO-2 observations of a field which is over-dense in Lyman Break Galaxies (LBGs) at z~5. The field includes seven spectroscopically-confirmed LBGs contained within a narrow (z=4.95+/-0.08) redshift range and an eighth at z=5.2. We do not detect any individual source to a limit of 1.6 mJy/beam (2*rms). When stacking the flux from the positions of all eight galaxies, we obtain a limit to the average 1.2 mm flux of these sources of 0.6mJy/beam. This limit is consistent with FIR imaging in other fields which are over-dense in UV-bright galaxies at z~5. Independently and combined, these limits constrain the FIR luminosity (8-1000 micron) to a typical z~5 LBG of LFIR<~3x10^11 Lsun, implying a dust mass of Mdust<~10^8 Msun (both assuming a grey body at 30K). This LFIR limit is an order of magnitude fainter than the LFIR of lower redshift sub-mm sources (z~1-3). We see no emission from any other sources within the field at the above level. While this is not unexpected given millimetre source counts, the clustered LBGs trace significantly over-dense large scale structure in the field at z = 4.95. The lack of any such detection in either this or the previous work, implies that massive, obscured star-forming galaxies may not always trace the same structures as over-densities of LBGs, at least on the length scale probed here. We briefly discuss the implications of these results for future observations with ALMA.Comment: 10 pages, 6 figures, MNRAS Accepte