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Community Health Workers And MHealth to ImProve Viral Suppression Plus (CHAMPS+)

ClinicalTrials.gov study NCT06472206. IPD Sharing: Not stated. Countries: 1. Publications: 0.

The Colorectal Cancer Chemoprevention Acceleration and Improvement Platform (CRC-CHAMP) Study

ClinicalTrials.gov study NCT05402124. IPD Sharing: NO. Countries: 1. Publications: 0.

A Study of RNK05047 in Subjects With Advanced Solid Tumors/Diffuse Large B-cell Lymphoma (CHAMP-1)

ClinicalTrials.gov study NCT05487170. IPD Sharing: NO. Countries: 2. Publications: 0.

Comprehensive Health Assessment for My Plan: Initial Implementation Study (CHAMP Implementation Study)

ClinicalTrials.gov study NCT06464471. IPD Sharing: NO. Countries: 1. Publications: 0.

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The Baby CHAMP Study (Children With Hemiparesis Arm and Movement Project)

ClinicalTrials.gov study NCT02346825. IPD Sharing: Not stated. Countries: 1. Publications: 0.

Implementation of Asthma Community Home and School Management Program (Asthma CHAMPS)

ClinicalTrials.gov study NCT05814510. IPD Sharing: NO. Countries: 1. Publications: 0.

CHAMP (Chandra Multiwavelength Project) Hard X-Ray Emitting AGN

This table contains the results from an X-ray and optical analysis of 188 active galactic nuclei (AGN) identified from 497 hard X-ray (observed flux in the (2.0 - 8.0 keV) band > 2.7 x 10-15 erg/cm2/s) sources in 20 Chandra fields (1.5 square degrees) forming part of the Chandra Multiwavelength Project (ChaMP). These medium-depth X-ray observations enable the detection of a representative subset of those sources responsible for the bulk of the 2 - 8 keV cosmic X-ray background. Brighter than the survey's optical spectroscopic limit, the authors achieve a reasonable degree of completeness (77% of X-ray sources with counterparts r' < 22.5 have been classified): broad emission-line AGNs (62%), narrow emission-line galaxies (24%), absorption-line galaxies (7%), stars (5%), or clusters (2%). To construct a pure AGN sample, the authors required the rest-frame 2.0-8.0 keV luminosity (uncorrected for intrinsic absorption) to exceed 1042 erg s-1, thereby excluding any sources that may contain a significant stellar or hot ISM component. The most luminous known star-forming or elliptical galaxies attain at most LX = 1042 erg s-1. Since many of the traditional optical AGN signatures are not present in obscured sources, high X-ray luminosity becomes the authors' single discriminant for supermassive black hole accretion. They believe that almost all of the NELGs and ALGs harbor accreting SMBHs based on their X-ray luminosity. They find that 90% of the identified ChaMP sources have luminosities above this threshold. These selection criteria yield a sample of 188 AGNs from 20 Chandra fields with f(2-8 keV) > 2.7 x 10-15 erg cm-2 s-1, r' < 22.5, and LX > 1042 erg s-1. The authors removed five objects identified as clusters based on their extended X-ray emission. This table was created by the HEASARC in March 2007 based on the CDS table J/ApJ/618/123, file table4.dat. This is a service provided by NASA HEASARC .

CHAMP/SDSS Nearby Low-Luminosity AGN Catalog

The combination of the Sloan Digital Sky Survey (SDSS) and the Chandra Multiwavelength Project (ChaMP; Green et al. 2004, ApJS, 150, 43) currently offers the largest and most homogeneously selected sample of nearby galaxies for investigating the relations between X-ray nuclear emission, nebular line emission, black hole masses, and the properties of the associated stellar populations. The authors provide X-ray spectral fits and valid uncertainties for all the galaxies with counts ranging from 2 to 1325 (mean 76, median 19). They present in their paper novel constraints that both X-ray luminosity LX and X-ray spectral energy distribution bring to the galaxy evolutionary sequence HII -> Seyfert/Transition Object -> LINER -> Passive suggested by optical data. In particular, the authors show that both LX and Gamma, the slope of the power law that best fits the 0.5 - 8 keV spectra, are consistent with a clear decline in the accretion power along the sequence, corresponding to a softening of their spectra. This implies that, at z ~ 0, or at low-luminosity active galactic nucleus (AGN) levels, there is an anticorrelation between Gamma and L/LEdd, opposite to the trend which is exhibited by high-z AGN (quasars). The turning point in the Gamma - L/LEdd LLAGN + quasars relation occurs near Gamma ~ 1.5 and L/LEdd ~ 0.01. Interestingly, this is identical to what stellar mass X-ray binaries exhibit, indicating that the authors have probably found the first empirical evidence for an intrinsic switch in the accretion mode, from advection-dominated flows to standard (disk/corona) accretion modes in supermassive black hole accretors, similar to what has been seen and proposed to happen in stellar mass black hole systems. The anticorrelation the authors find between Gamma and L/LEdd may instead indicate that stronger accretion correlates with greater absorption. Therefore, the trend for softer spectra toward more luminous, high-redshift, and strongly accreting (L/LEdd >~ 0.01) AGNs/quasars could simply be the result of strong selection biases reflected in the dearth of type 2 quasar detections. The cross-match of all ChaMP sky regions imaged by Chandra/ACIS with the SDSS DR4 spectroscopic footprint results in a parent sample of 15,955 galaxies on or near a chip and a subset of 199 sources that are X-ray detected. Among those, only 107 sources have an off-axis angle (OAA) Theta <0.2 degrees and avoid ccd=8 due to high serial readout noise; these 107 objects comprise the main sample that the authors employ for this study and that are listed in this table. The authors performed direct spectral fits to the X-ray counts distribution using the full instrument calibration, known redshift, and Galactic 21-cm column nHGal. Source spectra were extracted from circular regions with radii corresponding to energy encircled fractions of ~90%, while the background region encompasses a 20 arcsec annulus, centered on the source, with separation 4 arcsecs, from the source region. Any nearby sources were excised, from both the source and the background regions. The spectral fitting was done via yaxx ('Yet Another X-ray eXtractor': Aldcroft 2006, BAAS, 38, 376), an automated script that employs the CIAO Sherpa tool. Each spectrum was fitted in the range 0.5 - 8 keV by two different models: (1) a single power law plus absorption fixed at the Galactic 21-cm value (model 'PL'), and (2) a fixed power law of photon index Gamma = 1.9 plus intrinsic absorption of column nH (model 'PLfix'). For the nine objects with more than 200 counts, the authors employed a third model in which both the slope of the power law and the intrinsic absorption were free to vary (model 'PL_abs'). This table was created by the HEASARC in January 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/705/1336/">CDS Catalog J/ApJ/705/1336/</a> file table1.dat. This is a service provided by NASA HEASARC .

Chandra Multiwavelength Project (ChaMP) Point Source Catalog

This table represents the `Main Chandra Multiwavelength Project (ChaMP) X-Ray Point Source Catalog' and contains the basic parameters, photometry, and fluxes of 6512 ChaMP sources in 130 Chandra observations from Chandra Cycles 1 and 2. This table lists fluxes for 2 assumed spectral energy distributions with the photon indices of Gamma=1.4 and Gamma=1.7. This catalog was distributed by the ChaMP team based on the "Chandra Multiwavelength Project: X-ray Point Source Catalog (Kim et al., 2007, ApJS, 169, 401)", and was downloaded from <a href="http://hea-www.harvard.edu/CHAMP/">http://hea-www.harvard.edu/CHAMP/</a>. If you have any comments/questions on this catalog, please contact mkim @ cfa.harvard.edu or dkim @ cfa.harvard.edu. The full Chandra Multiwavelength Project (ChaMP) X-ray point source catalog lists ~ 6800 X-ray sources detected in 149 Chandra observations covering ~ 10 square degrees. The full ChaMP catalog sample is 7 times larger than the initial published ChaMP catalog (Kim et al. 2004, ApJS, 150, 19). The exposure times of the fields in this sample range from 0.9 to 124 ks, corresponding to a deepest X-ray flux limit in the 0.5 - 8.0 keV band of 9 x 10-16 ergs cm-2 s-1. The ChaMP X-ray data were uniformly reduced and analyzed with ChaMP-specific pipelines and then carefully validated by visual inspection. The ChaMP catalog includes X-ray photometric data in eight different energy bands as well as X-ray spectral hardness ratios and colors, source reliability, detection probability, and positional uncertainties. The false source detection rate is ~1% of all detected ChaMP sources, while the detection probability is better than ~ 95% for sources with counts >~ 30 and off-axis angle <5'. The typical positional offset between ChaMP X-ray source and their SDSS optical counterparts is 0.7" +/- 0.4", derived from ~ 900 matched sources. This HEASARC table contains the main ChaMP catalog of 6512 X-ray point sources in 130 ChaMP fields observed once and in the overlapping fields which had the longest exposures. It does not contain the supplementary ChaMP catalog of 853 sources in 19 ChaMP overlapping fields with shorter exposure times. This table was created by the HEASARC in October 2006 based on the table <a href="http://hea-www.cfa.harvard.edu/CHAMP/IMAGES_DATA/champ_xpc.tab">http://hea-www.cfa.harvard.edu/CHAMP/IMAGES_DATA/champ_xpc.tab</a> on the ChaMP website. This is a service provided by NASA HEASARC .

ChaMP Extended Stellar Survey (ChESS) X-Ray Catalog

The ChaMP Extended Stellar Survey (ChESS) X-ray catalog contains 348 X-ray-emitting stars identified from correlating the Extended Chandra Multiwavelength Project (ChaMP), a wide-area serendipitous survey based on archival X-ray images, with the Sloan Digital Sky Survey (SDSS). The authors used morphological star/galaxy separation, matching to an SDSS quasar catalog, an optical color-magnitude cut, and X-ray data-quality tests to create this catalog, from a sample of 2121 matched ChaMP/SDSS sources. Their cuts retain 92% of the spectroscopically confirmed stars in the original sample while excluding 99.6% of the 684 spectroscopically confirmed extragalactic sources. Fewer than 3% of the sources in their final catalog are previously identified stellar X-ray emitters. For 42 catalog members, spectroscopic classifications are available in the literature. New spectral classifications and H-alpha measurements are presented for an additional 79 stars. The catalog is dominated by main-sequence stars; the authors estimate the fraction of giants in ChESS to be ~10%. They identify seven giant stars (including a possible Cepheid and an RR Lyrae star) as ChaMP sources, as well as three cataclysmic variables. They derive distances from ~10 to 2000 pc for the stars in the catalog using photometric parallax relations appropriate for dwarfs on the main sequence and calculate their X-ray and bolometric luminosities. These stars lie in a unique space in the LX-distance plane, filling the gap between the nearby stars identified as counterparts to sources in the ROSAT All Sky Survey and the more distant stars detected in deep Chandra and XMM-Newton surveys. For 36 newly identified X-ray-emitting M stars, the authors calculated LH-alpha/Lbol. The quantities LH-alpha/Lbol and LX/Lbol are linearly related below LX/Lbol ~ 3 x 10-4, while LH-alpha/Lbol appears to turn over at larger LX/Lbol values. Stars with reliable SDSS photometry have an ~0.1 mag blue excess in u-g, likely due to increased chromospheric continuum emission. Photometric metallicity estimates suggest that the sample is evenly split between the young and old disk populations of the Galaxy; the lowest activity sources belong to the old disk population, a clear signature of the decay of magnetic activity with age. This table was created by the HEASARC in January 2009 based on the electronic version of Tables 2 and 3 from the reference paper which were obtained from the ApJ web site. This is a service provided by NASA HEASARC .