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Supernova pencil beam survey  [PDF]
Yun Wang
Physics , 1998, DOI: 10.1086/308500
Abstract: Type Ia supernovae (SNe Ia) can be calibrated to be good standard candles at cosmological distances. We propose a supernova pencil beam survey that could yield between dozens to hundreds of SNe Ia in redshift bins of 0.1 up to $z=1.5$, which would compliment space based SN searches, and enable the proper consideration of the systematic uncertainties of SNe Ia as standard candles, in particular, luminosity evolution and gravitational lensing. We simulate SNe Ia luminosities by adding weak lensing noise (using empirical fitting formulae) and scatter in SN Ia absolute magnitudes to standard candles placed at random redshifts. We show that flux-averaging is powerful in reducing the combined noise due to gravitational lensing and scatter in SN Ia absolute magnitudes. The SN number count is not sensitive to matter distribution in the universe; it can be used to test models of cosmology or to measure the SN rate. The SN pencil beam survey can yield a wealth of data which should enable accurate determination of the cosmological parameters and the SN rate, and provide valuable information on the formation and evolution of galaxies. The SN pencil beam survey can be accomplished on a dedicated 4 meter telescope with a square degree field of view. This telescope can be used to conduct other important observational projects compatible with the SN pencil beam survey, such as QSOs, Kuiper belt objects, and in particular, weak lensing measurements of field galaxies, and the search for gamma-ray burst afterglows.
Paper-and-pencil cosmological calculator  [PDF]
Sergey V. Pilipenko
Physics , 2013,
Abstract: The paper-and-pencil calculator is a cosmological nomogram which allows to find relations between redshift, distance, age of the Universe, physical and angular sizes, luminosity and apparent magnitude for the standard cosmological model with parameters from the Planck mission.
The use of research questionnaires with hearing impaired adults: online vs. paper-and-pencil administration  [cached]
Thorén Elisabet,Andersson Gerhard,Lunner Thomas
BMC Ear, Nose and Throat Disorders , 2012, DOI: 10.1186/1472-6815-12-12
Abstract: Background When evaluating hearing rehabilitation, it is reasonable to use self-report questionnaires as outcome measure. Questionnaires used in audiological research are developed and validated for the paper-and-pencil format. As computer and Internet use is increasing, standardized questionnaires used in the audiological context should be evaluated to determine the viability of the online administration format. The aim of this study was to compare administration of questionnaires online versus paper- and pencil of four standardised questionnaires used in hearing research and clinic. We included the Hearing Handicap Inventory for the Elderly (HHIE), the International Outcome Inventory for Hearing Aids (IOI-HA), Satisfaction with Amplification in Daily Life (SADL), and the Hospital Anxiety and Depression Scale (HADS). Methods A cross-over design was used by randomly letting the participants complete the questionnaires either online or on paper. After 3 weeks the participants filled out the same questionnaires again but in the other format. A total of 65 hearing-aid users were recruited from a hearing clinic to participate on a voluntary basis and of these 53 completed both versions of the questionnaires. Results A significant main effect of format was found on the HHIE (p < 0.001), with participants reporting higher scores on the online format than in the paper format. There was no interaction effect. For the other questionnaires were no significant main or interaction effects of format. Significant correlations between the two ways of presenting the measures was found for all questionnaires (p<0.05). The results from reliability tests showed Cronbachs α’s above .70 for all four questionnaires and differences in Cronbachs α between administration formats were negligible. Conclusions For three of the four included questionnaires the participants’ scores remained consistent across administrations and formats. For the fourth included questionnaire (HHIE) a significant difference of format with a small effect size was found. The relevance of the difference in scores between the formats depends on which context the questionnaire is used in. On balance, it is recommended that the administration format remain stable across assessment points.
Psychometric comparison of paper-and-pencil and online personality assessments in a selection setting  [cached]
Tina Joubert,Hendrik J. Kriek
South African Journal of Industrial Psychology , 2009, DOI: 10.4102/sajip.v35i1.727
Abstract: The goal of the study was to determine whether the Occupational Personality Questionnaire (OPQ32i) yielded comparable results when two different modes of administration, namely paper and-pencil and Internet- based administration, were used in real-life, high-stakes selection settings. Two studies were conducted in which scores obtained online in unproctored settings were compared with scores obtained during proctored paper-and-pencil settings. The psychometric properties of the paper-and-pencil and Internet-based applications were strikingly similar. Structural equation modelling with EQS indicated substantial support for the hypothesis that covariance matrices of the paper-and-pencil and online applications in both studies were identical. It was concluded that relationships between the OPQ32i scales were not affected by mode of administration or supervision. How to cite this article: Joubert, T., & Kriek, H.J. (2009). Psychometric comparison of paper and-pencil and online personality assessments in a selection setting. SA Journal of Industrial Psychology/ SA Tydskrif vir Bedryfsielkunde, 35(1), Art. #727, 11 pages. DOI: 10.4102/sajip.v35i1.727
A Spitzer Unbiased Ultradeep Spectroscopic Survey  [PDF]
B. Bertincourt,G. Helou,P. Appleton,P. Ogle,G. Lagache,T. Brooke,J. -D. Smith,K. Sheth,D. Dale,M. Harwit,J. -L. Puget,H. Roussel
Physics , 2009, DOI: 10.1088/0004-637X/705/1/68
Abstract: We carried out an unbiased, spectroscopic survey using the low-resolution module of the infrared spectrograph (IRS) on board Spitzer targeting two 2.6 square arcminute regions in the GOODS-North field. IRS was used in spectral mapping mode with 5 hours of effective integration time per pixel. One region was covered between 14 and 21 microns and the other between 20 and 35 microns. We extracted spectra for 45 sources. About 84% of the sources have reported detections by GOODS at 24 microns, with a median F_nu(24um) ~ 100 uJy. All but one source are detected in all four IRAC bands, 3.6 to 8 microns. We use a new cross-correlation technique to measure redshifts and estimate IRS spectral types; this was successful for ~60% of the spectra. Fourteen sources show significant PAH emission, four mostly SiO absorption, eight present mixed spectral signatures (low PAH and/or SiO) and two show a single line in emission. For the remaining 17, no spectral features were detected. Redshifts range from z ~ 0.2 to z ~ 2.2, with a median of 1. IR Luminosities are roughly estimated from 24 microns flux densities, and have median values of 2.2 x 10^{11} L_{\odot} and 7.5 x 10^{11} L_{\odot} at z ~ 1 and z ~ 2 respectively. This sample has fewer AGN than previous faint samples observed with IRS, which we attribute to the fainter luminosities reached here.
Keck Pencil-Beam Survey for Faint Kuiper Belt Objects  [PDF]
E. I. Chiang,M. E. Brown
Physics , 1999, DOI: 10.1086/301005
Abstract: We present the results of a pencil-beam survey of the Kuiper Belt using the Keck 10-m telescope. A single 0.01 square degree field is imaged 29 times for a total integration time of 4.8 hr. Combining exposures in software allows the detection of Kuiper Belt Objects (KBOs) having visual magnitude V < 27.9. Two new KBOs are discovered. One object having V = 25.5 lies at a probable heliocentric distance d = 33 AU. The second object at V = 27.2 is located at d = 44 AU. Both KBOs have diameters of about 50 km, assuming comet-like albedos of 4%. Data from all surveys are pooled to construct the luminosity function from red magnitude R = 20 to 27. The cumulative number of objects per square degree, N (< R), is fitted to a power law of the form log_(10) N = 0.52 (R - 23.5). Differences between power laws reported in the literature are due mainly to which survey data are incorporated, and not to the method of fitting. The luminosity function is consistent with a power-law size distribution for objects having diameters s = 50 to 500 km; dn ~ s^(-q) ds, where the differential size index q = 3.6 +/- 0.1. The distribution is such that the smallest objects possess most of the surface area, but the largest bodies contain the bulk of the mass. Though our inferred size index nearly matches that derived by Dohnanyi (1969), it is unknown whether catastrophic collisions are responsible for shaping the size distribution. Implications of the absence of detections of classical KBOs beyond 50 AU are discussed.
Does Assessment Type Matter? A Measurement Invariance Analysis of Online and Paper and Pencil Assessment of the Community Assessment of Psychic Experiences (CAPE)  [PDF]
Marloes Vleeschouwer, Chris D. Schubart, Cecile Henquet, Inez Myin-Germeys, Willemijn A. van Gastel, Manon H. J. Hillegers, Jim J. van Os, Marco P. M. Boks, Eske M. Derks
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0084011
Abstract: Background The psychometric properties of an online test are not necessarily identical to its paper and pencil original. The aim of this study is to test whether the factor structure of the Community Assessment of Psychic Experiences (CAPE) is measurement invariant with respect to online vs. paper and pencil assessment. Method The factor structure of CAPE items assessed by paper and pencil (N = 796) was compared with the factor structure of CAPE items assessed by the Internet (N = 21,590) using formal tests for Measurement Invariance (MI). The effect size was calculated by estimating the Signed Item Difference in the Sample (SIDS) index and the Signed Test Difference in the Sample (STDS) for a hypothetical subject who scores 2 standard deviations above average on the latent dimensions. Results The more restricted Metric Invariance model showed a significantly worse fit compared to the less restricted Configural Invariance model (χ2(23) = 152.75, p<0.001). However, the SIDS indices appear to be small, with an average of ?0.11. A STDS of ?4.80 indicates that Internet sample members who score 2 standard deviations above average would be expected to score 4.80 points lower on the CAPE total scale (ranging from 42 to 114 points) than would members of the Paper sample with the same latent trait score. Conclusions Our findings did not support measurement invariance with respect to assessment method. Because of the small effect sizes, the measurement differences between the online assessed CAPE and its paper and pencil original can be neglected without major consequences for research purposes. However, a person with a high vulnerability for psychotic symptoms would score 4.80 points lower on the total scale if the CAPE is assessed online compared to paper and pencil assessment. Therefore, for clinical purposes, one should be cautious with online assessment of the CAPE.
The optically unbiased GRB host (TOUGH) survey. I. Survey design and catalogs  [PDF]
Jens Hjorth,Daniele Malesani,Páll Jakobsson,Andreas O. Jaunsen,Johan P. U. Fynbo,Javier Gorosabel,Thomas Krühler,Andrew J. Levan,Micha? J. Micha?owski,Bo Milvang-Jensen,Palle M?ller,Steve Schulze,Nial R. Tanvir,Darach Watson
Physics , 2012, DOI: 10.1088/0004-637X/756/2/187
Abstract: Long-duration gamma-ray bursts (GRBs) are powerful tracers of star-forming galaxies. We have defined a homogeneous subsample of 69 Swift GRB-selected galaxies spanning a very wide redshift range. Special attention has been devoted to making the sample optically unbiased through simple and well-defined selection criteria based on the high-energy properties of the bursts and their positions on the sky. Thanks to our extensive follow-up observations, this sample has now achieved a comparatively high degree of redshift completeness, and thus provides a legacy sample, useful for statistical studies of GRBs and their host galaxies. In this paper we present the survey design and summarize the results of our observing program conducted at the ESO Very Large Telescope (VLT) aimed at obtaining the most basic properties of galaxies in this sample, including a catalog of R and Ks magnitudes and redshifts. We detect the host galaxies for 80 % of the GRBs in the sample, although only 42 % have Ks-band detections, which confirms that GRB-selected host galaxies are generally blue. The sample is not uniformly blue, however, with two extremely red objects detected. Moreover, galaxies hosting GRBs with no optical/NIR afterglows, whose identification therefore relies on X-ray localizations, are significantly brighter and redder than those with an optical/NIR afterglow. Our spectroscopic campaign has resulted in 77 % now having redshift measurements, with a median redshift of 2.14 +- 0.18. TOUGH alone includes 17 detected z > 2 Swift GRB host galaxies suitable for individual and statistical studies. Seven hosts have detections of the Ly-alpha emission line and we can exclude an early indication that Ly-alpha emission is ubiquitous among GRB hosts, but confirm that Ly-alpha is stronger in GRB-selected galaxies than in flux-limited samples of Lyman break galaxies.
Multi Graphene Growth on Lead Pencil Drawn Sliver-Halide Print Paper Irradiated by Scanning Femtosecond Laser  [PDF]
Satoru Kaneko,Yoshitada Shimizu,Takeshi Rachi,Chihiro Kato,Satomi Tanaka,Yasuhiro Naganuma,Toru Katakura,Kazuo Satoh,Mikio Ushiyama,Seiji Konuma,Yuko Itou,Hirofumi Takikawa,Goon Tan,Akifumi Matsuda,Mamoru Yoshimoto
Physics , 2015,
Abstract: A variety of paper were drawn by lead pencil with the grade between 4H through 10B. Raman spectroscopy verified both G and D peaks on all the drawing on PC print paper, PC photo paper, kent paper and paper for silver halide print. After irradiation of scanning femtosecond laser, silver halide paper drawn with 10B lead pencil remained surface flatness compared to the other papers. Raman spectroscopy on silver print paper showed a large G peak with less intensity of D peak. After irradiation of scanning femtosecond laser on silver halide paper drawn by 10B lead pencil, Raman spectroscopy showed large G peak and less intensity of D peak together with 2D peak around 2,700 /cm corresponding to the existence of multi graphene.
Finding halo streams with a pencil-beam survey: new wraps in the Sagittarius stream  [PDF]
B. Pila-Díez,K. Kuijken,J. T. A. de Jong,H. Hoekstra,R. F. J. van der Burg
Physics , 2013, DOI: 10.1051/0004-6361/201323000
Abstract: We use data from two CFHT-MegaCam photometric pencil-beam surveys in the g' and the r' bands to measure distances to the Sagittarius, the Palomar 5 and the Orphan stream. We show that, using a cross-correlation algorithm to detect the turnoff point of the main sequence, it is possible to overcome the main limitation of a two-bands pencil-beam survey, namely the lack of adjacent control-fields that can be used to subtract the foreground and background stars to enhance the signal on the colour-magnitude diagrams (CMDs). We describe the cross-correlation algorithm and its implementation. We combine the resulting main sequence turnoff points with theoretical isochrones to derive photometric distances to the streams. Our results (31 detections on the Sagittarius stream and one each for the Palomar 5 and the Orphan streams) confirm the findings by previous studies, expand the distance trend for the Sagittarius faint southern branch and, for the first time, trace the Sagittarius faint branch of the northern-leading arm out to 56 kpc. In addition, they show evidence for new substructure: we argue that these detections trace the continuation of the Sagittarius northern-leading arm into the southern hemisphere, and find a nearby branch of the Sagittarius trailing wrap in the northern hemisphere.
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