Cross-correlation of Gaia DR3 Stellar Halo with Fermi LAT Gamma-ray Halo Template: Evidence for Halo-Specific Spatial Correlation at 4.7σ Outside Fermi Bubble Region

Key Points

• The research aims to investigate the spatial correlation between the Gaia DR3 stellar halo and the Fermi LAT gamma-ray halo template, particularly outside the Fermi bubble region.
• Utilized full Totani ROI involving both hemispheres and 10,535 pixels
• Employed Spearman's rank correlation analysis to assess correlation strength
• Applied block bootstrap techniques for statistical significance
• Controlled for latitude in measuring partial correlations
• Found a raw Spearman correlation coefficient of 0.337, indicating moderate correlation
• Achieved a significant halo-specific correlation of 4.7σ after strict selection
• Outside the Fermi bubble region, the correlation showed a partial coefficient of 0.065 at 2.6σ
• Disk stars analysis yielded a correlation that included zero, suggesting no significant signal