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تسجيل مستخدم جديدCHIME/FRB Catalog 1 results: statistical cross-correlations with large-scale structure
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The CHIME/FRB Project has recently released its first catalog of fast radio bursts (FRBs), containing 492 unique sources. We present results from angular cross-correlations of CHIME/FRB sources with galaxy catalogs. We find a statistically significant ($p$-value $sim 10^{-4}$, accounting for look-elsewhere factors) cross-correlation between CHIME FRBs and galaxies in the redshift range $0.3 lesssim z lesssim 0.5$, in three photometric galaxy surveys: WISE$times$SCOS, DESI-BGS, and DESI-LRG. The level of cross-correlation is consistent with an order-one fraction of the CHIME FRBs being in the same dark matter halos as survey galaxies in this redshift range. We find statistical evidence for a population of FRBs with large host dispersion measure ($sim 400$ pc cm$^{-3}$), and show that this can plausibly arise from gas in large halos ($M sim 10^{14} M_odot$), for FRBs near the halo center ($r lesssim 100$ kpc). These results will improve in future CHIME/FRB catalogs, with more FRBs and better angular resolution.
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