Kavli Affiliate: Renxin Xu | Summary:We discover an intrinsic degeneracy in the semi-analytic two-spot model for parameter inference in thermal X-ray pulse-profile modeling. Although this degeneracy exists in our simplified model with two small circular hot spots and without Doppler effects, it causes the likelihood surface of parameter inference based on ST-U and more complex […]

Kavli Affiliate: Renxin Xu | Summary:We identify an intrinsic degeneracy in the simplified semi-analytic two-spot model for parameter inference in thermal X-ray pulse-profile modeling. Although the exact algebraic degeneracy exists in our simplified model without Doppler effects, we generate synthetic pulse-profiles and show that this degeneracy can still result in two peaks on the likelihood […]

Kavli Affiliate: Renxin Xu | Summary:We identify an intrinsic degeneracy in the simplified semi-analytic two-spot model for parameter inference in thermal X-ray pulse-profile modeling. Although the exact algebraic degeneracy exists in our simplified model without Doppler effects, we generate synthetic pulse-profiles and show that this degeneracy can still result in two peaks on the likelihood […]

Kavli Affiliate: Claudio Ricci | Summary:We utilize JWST/MIRI IFU observations from the Galaxy Activity, Torus and Outflow Survey (GATOS) to investigate the diverse range of ionized outflow rates of obscured AGN with similar bolometric luminosity and explore potential associations with AGN feedback. We explore spatial correlations between ionized emission potentially associated with fast shocks ([Fe […]

Kavli Affiliate: Luis Ho | Summary:We construct a catalog of mid-infrared (MIR) variable sources using the multi-epoch 3.6 (W1) and 4.5 $μ$m (W2) dataset from the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) at the north and south ecliptic poles (NEP and SEP). The catalog provides well-sampled light curves that cover areas within a radius […]

Kavli Affiliate: Feng Long| Summary: We study high-dimensional regression in principal components space when the predictors are observed with additive measurement error and the response errors may be heavy-tailed. The starting point is the $ell_1$-penalized principal-components estimator of Song and Zou (2026), which enjoys a blessing-of-dimensionality phenomenon under predictor contamination but senstive for heavy-tailed data […]

Kavli Affiliate: Feng Long| Summary: We study bootstrap inference for the $k$th largest coordinate of a normalized sum of independent high-dimensional random vectors. Existing second-order theory for maxima does not directly extend to order statistics, because the event $T_n,[k]le t$ is not a rectangle and its local structure is governed by exceedance counts rather than […]

Kavli Affiliate: Luis Ho | Summary:In this letter, we report a novel discovery of unique characteristics for the tidal dwarf galaxy (candidate) Holmberg IX via a multiwavelength investigation. New observations are taken for deeply mapping Hα emission and combined with archival/published data for comprehensively probing dust, gas, and stellar populations in this galaxy. We find […]

Kavli Affiliate: Luis Ho | Summary:In this Letter, we report a novel discovery of unique characteristics for the tidal dwarf galaxy (candidate) Holmberg IX via a multiwavelength investigation. New observations are taken for deeply mapping Hα emission and combined with archival/published data for comprehensively probing dust, gas, and stellar populations in this galaxy. We find […]

Kavli Affiliate: Fukun Liu| Summary: We present a multi-epoch study of the extreme X-ray variability of the type~1 quasar SDSS~J000532.84+200717.4 using archival observations from textitXMM-Newton, textitSwift/XRT, textitEP-FXT, and textitROSAT, together with new optical spectroscopy and multi-wavelength photometry. The 0.2–10~keV X-ray flux exhibits a transition from a high state to a subsequent low state, declining by […]