UBVRI photometric standard stars in the magnitude range 11.5-16.0 around the celestial equator

1992 ◽  
Vol 104 ◽  
pp. 340 ◽  
Author(s):  
Arlo U. Landolt
1978 ◽  
Vol 48 ◽  
pp. 421-432 ◽  
Author(s):  
W. Fricke ◽  
W. Gliese

Abstract:Presented is a status report on work on FK5 giving information on the following items: (a) the intended increase of the number of fundamental stars and their magnitude range in FK5, (b) available material for the improvement of the system, (c) methods for the determination of systematic differences, (d) the determination of equator and equinox of FK5, and (e) the elimination of the motion of the FK4 equinox.


2013 ◽  
Vol 765 (1) ◽  
pp. 67 ◽  
Author(s):  
Felipe Menanteau ◽  
Cristóbal Sifón ◽  
L. Felipe Barrientos ◽  
Nicholas Battaglia ◽  
J. Richard Bond ◽  
...  

2019 ◽  
Vol 489 (2) ◽  
pp. 2887-2906 ◽  
Author(s):  
S Lee ◽  
E M Huff ◽  
A J Ross ◽  
A Choi ◽  
C Hirata ◽  
...  

ABSTRACT We present a sample of galaxies with the Dark Energy Survey (DES) photometry that replicates the properties of the BOSS CMASS sample. The CMASS galaxy sample has been well characterized by the Sloan Digital Sky Survey (SDSS) collaboration and was used to obtain the most powerful redshift-space galaxy clustering measurements to date. A joint analysis of redshift-space distortions (such as those probed by CMASS from SDSS) and a galaxy–galaxy lensing measurement for an equivalent sample from DES can provide powerful cosmological constraints. Unfortunately, the DES and SDSS-BOSS footprints have only minimal overlap, primarily on the celestial equator near the SDSS Stripe 82 region. Using this overlap, we build a robust Bayesian model to select CMASS-like galaxies in the remainder of the DES footprint. The newly defined DES-CMASS (DMASS) sample consists of 117 293 effective galaxies covering $1244\,\deg ^2$. Through various validation tests, we show that the DMASS sample selected by this model matches well with the BOSS CMASS sample, specifically in the South Galactic cap (SGC) region that includes Stripe 82. Combining measurements of the angular correlation function and the clustering-z distribution of DMASS, we constrain the difference in mean galaxy bias and mean redshift between the BOSS CMASS and DMASS samples to be $\Delta b = 0.010^{+0.045}_{-0.052}$ and $\Delta z = \left(3.46^{+5.48}_{-5.55} \right) \times 10^{-3}$ for the SGC portion of CMASS, and $\Delta b = 0.044^{+0.044}_{-0.043}$ and $\Delta z= (3.51^{+4.93}_{-5.91}) \times 10^{-3}$ for the full CMASS sample. These values indicate that the mean bias of galaxies and mean redshift in the DMASS sample are consistent with both CMASS samples within 1σ.


2019 ◽  
Vol 6 (2) ◽  
pp. 211-218 ◽  
Author(s):  
Chloe S. Coates ◽  
Andrew L. Goodwin

Negative thermal expansion (NTE) is the counterintuitive material property of volume contraction on heating. We compare different systems with contrasting mechanisms for isotropic NTE using the metric of NTE capacity.


1989 ◽  
Vol 42 (4) ◽  
pp. 439 ◽  
Author(s):  
R Brahde

In an earlier paper (Brahde 1988) it was shown that series of measurements of the atmospheric pressure in Oslo contained information about a one�day oscillation with mean amplitude 0�17 mb. The data consisted of measurements every second hour during the years 1957-67, 1969 and 1977. In the present paper the intervening years plus 1978 and 1979 have been included, increasing the basis from 13 to 23 years. In addition the phase shift occurring when the Moon crosses the celestial equator has been defined precisely, thus making it possible to include all the data.


2012 ◽  
Vol 55 (1) ◽  
Author(s):  
Marco Massa ◽  
Gabriele Ameri ◽  
Sara Lovati ◽  
Rodolfo Puglia ◽  
Gianlorenzo Franceschina ◽  
...  

<p>This note focuses on the ground motion recorded during the recent moderate earthquakes that occurred in the central part of northern Italy (Panel 1), a region that is characterized by low seismicity. For this area, the Italian seismic hazard map [Stucchi et al. 2011] assigns a maximum horizontal acceleration (rock site) of up to 0.2 g (10% probability of being exceeded in 50 yr). In the last 4 yr, this region has been struck by 9 earthquakes in the magnitude range 4 <span>≤</span>M<span>w </span><span>≤</span> 5.0, with the three largest located in the Northern Apennines (the M<span>w </span>4.9 and 5.0 Parma events, in December 2008 and January 2012) and on the Po Plain (the M<span>w </span>4.9 Reggio Emila event, in January 2012). We have analyzed the strong-motion data (distance &lt;300 km) from these events as recorded by stations belonging to the Istituto Nazionale di Geofisica e Vulcanologia (RAIS, http://rais.mi.ingv.it; RSNC, http://iside.rm.ingv.it) and the Department of Civil Protection (RAN, www.protezionecivile.it; http://itaca.mi.ingv.it). […]</p>


2012 ◽  
Vol 55 (4) ◽  
Author(s):  
Silvia Pondrelli ◽  
Simone Salimbeni ◽  
Paolo Perfetti ◽  
Peter Danecek

<p>In May 2012, a seismic sequence struck the Emilia region (northern Italy). The mainshock, of Ml 5.9, occurred on May 20, 2012, at 02:03 UTC. This was preceded by a smaller Ml 4.1 foreshock some hours before (23:13 UTC on May 19, 2012) and followed by more than 2,500 earthquakes in the magnitude range from Ml 0.7 to 5.2. In addition, on May 29, 2012, three further strong earthquakes occurred, all with magnitude Ml ≥5.2: a Ml 5.8 earthquake in the morning (07:00 UTC), followed by two events within just 5 min of each other, one at 10:55 UTC (Ml 5.3) and the second at 11:00 UTC (Ml 5.2). For all of the Ml ≥4.0 earthquakes in Italy and for all of the Ml ≥4.5 in the Mediterranean area, an automatic procedure for the computation of a regional centroid moment tensor (RCMT) is triggered by an email alert. Within 1 h of the event, a manually revised quick RCMT (QRCMT) can be published on the website if the solution is considered stable. In particular, for the Emilia seismic sequence, 13 QRCMTs were determined and for three of them, those with M &gt;5.5, the automatically computed QRCMTs fitted the criteria for publication without manual revision. Using this seismic sequence as a test, we can then identify the magnitude threshold for automatic publication of our QRCMTs.</p>


2021 ◽  
Vol 13 (12) ◽  
pp. 5509-5544
Author(s):  
Alberto Michelini ◽  
Spina Cianetti ◽  
Sonja Gaviano ◽  
Carlo Giunchi ◽  
Dario Jozinović ◽  
...  

Abstract. The Italian earthquake waveform data are collected here in a dataset suited for machine learning analysis (ML) applications. The dataset consists of nearly 1.2 million three-component (3C) waveform traces from about 50 000 earthquakes and more than 130 000 noise 3C waveform traces, for a total of about 43 000 h of data and an average of 21 3C traces provided per event. The earthquake list is based on the Italian Seismic Bulletin (http://terremoti.ingv.it/bsi, last access: 15 February 2020​​​​​​​) of the Istituto Nazionale di Geofisica e Vulcanologia between January 2005 and January 2020, and it includes events in the magnitude range between 0.0 and 6.5. The waveform data have been recorded primarily by the Italian National Seismic Network (network code IV) and include both weak- (HH, EH channels) and strong-motion (HN channels) recordings. All the waveform traces have a length of 120 s, are sampled at 100 Hz, and are provided both in counts and ground motion physical units after deconvolution of the instrument transfer functions. The waveform dataset is accompanied by metadata consisting of more than 100 parameters providing comprehensive information on the earthquake source, the recording stations, the trace features, and other derived quantities. This rich set of metadata allows the users to target the data selection for their own purposes. Much of these metadata can be used as labels in ML analysis or for other studies. The dataset, assembled in HDF5 format, is available at http://doi.org/10.13127/instance (Michelini et al., 2021).


2018 ◽  
Author(s):  
Chloe Coates ◽  
Andrew Goodwin

<div>Negative thermal expansion (NTE) is the useful and counterintuitive material property of volume contraction on heating. Isotropic NTE is the rarest and most useful type, and is known to occur in a variety of different classes of materials. In this mini-review we ask the simple question of how best to compare NTE behaviour amongst these different systems? We summarise the two main mechanisms for isotropic NTE, and illustrate how these favour alternatively NTE magnitude</div><div>and NTE range. We argue in favour of a combined metric of NTE capacity, which balances both effects and allows unbiased identification of the most remarkable NTE materials, irrespective of the underlying microscopic mechanism at play. By organising known NTE materials according to these various metrics, we find intuitive trends in behaviour that help identify key materials for specific NTE applications.</div>


1990 ◽  
Vol 80 (2) ◽  
pp. 340-353
Author(s):  
D. W. A. Taylor ◽  
J. A. Snoke ◽  
I. S. Sacks ◽  
T. Takanami

Abstract Frequency-magnitude relationships are determined for a source region defined by a circular epicentral area of 50 km radius centered on the Carnegie broadband seismograph at KMU in the southeast corner of Hokkaido Island, Japan. Within this region, bounded by a maximum depth of 125 km, more than 11,100 earthquakes were detected and cataloged by the Hokkaido University network during the period July 1976 through January 1987. The seismicity is divided into two effectively decoupled suites: crustal (Eurasian plate) and subduction (Pacific plate). The frequency-magnitude recurrence distributions exhibit departures from linearity which are statistically significant below md = 2.5 for the crustal data suite and md = 3.5 for the subduction data suite. Three independent tests show the nonlinearity is not caused by incompleteness; the catalog is complete down to magnitude 2.0 or less for both data suites. These observations are therefore inconsistent with the linear Gutenberg-Richter relationship, which is assumed to be valid over any magnitude range for which the data are complete. There are relatively more large events and fewer small events in the subduction suite. The logarithm of the ratio of the number of crustal events to the number of subduction events versus magnitude is monotonically decreasing and remarkably linear over the magnitude range 1.0 to 5.0. This suggests that the observed nonlinearity of these two frequency-magnitude relationships has a common origin.


Sign in / Sign up

Export Citation Format

Share Document