Pixel-based correction for Charge Transfer Inefficiency in the Hubble Space Telescope Advanced Camera for Surveys

Parallax of Galactic Cepheids from Spatially Scanning the Wide Field Camera 3 on the Hubble Space Telescope: The Case of SS Canis Majoris

We present a high-precision measurement of the parallax for the 12-day Cepheid SS Canis Majoris, obtained via spatial scanning with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). Spatial scanning enables astrometric measurements with a precision of 20-40 muas, an order of magnitude better than pointed observations. SS CMa is the second Cepheid targeted for parallax measurement with HST, and is the first of a sample of eighteen long-period >~ 10 days) Cepheids selected in order to improve the calibration of their period-luminosity relation and eventually permit a determinat…

Flexion measurement in simulations of Hubble Space Telescope data

We present a simulation analysis of weak gravitational lensing flexion and shear measurement using shapelet decomposition, and identify differences between flexion and shear measurement noise in deep survey data. Taking models of galaxies from the Hubble Space Telescope Ultra Deep Field (HUDF) and applying a correction for the HUDF point spread function we generate lensed simulations of deep, optical imaging data from Hubble's Advanced Camera for Surveys (ACS), with realistic galaxy morphologies. We find that flexion and shear estimates differ in our measurement pipeline: whereas intrinsic gal…

Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with LambdaCDM

We present an expanded sample of 75 Milky Way Cepheids with Hubble Space Telescope (HST) photometry and Gaia EDR3 parallaxes which we use to recalibrate the extragalactic distance ladder and refine the determination of the Hubble constant. All HST observations were obtained with the same instrument (WFC3) and filters (F555W, F814W, F160W) used for imaging of extragalactic Cepheids in Type Ia supernova (SN Ia) hosts. The HST observations used the WFC3 spatial scanning mode to mitigate saturation and reduce pixel-to-pixel calibration errors, reaching a mean photometric error of 5 millimags per o…

Milky Way Cepheid Standards for Measuring Cosmic Distances and Application to Gaia DR2: Implications for the Hubble Constant

We present HST photometry of a selected sample of 50 long-period, low-extinction Milky Way Cepheids measured on the same WFC3 F555W, F814W, and F160W-band photometric system as extragalactic Cepheids in SN Ia hosts. These bright Cepheids were observed with the WFC3 spatial scanning mode in the optical and near-infrared to mitigate saturation and reduce pixel-to-pixel calibration errors to reach a mean photometric error of 5 millimags per observation. We use the new Gaia DR2 parallaxes and HST photometry to simultaneously constrain the cosmic distance scale and to measure the DR2 parallax zerop…

Quantitative Method for the Optimal Subtraction of Continuum Emission from Narrow-band Images : Skewness Transition Analysis

We present an objective method to remove the stellar continuum emission from narrow-band images to derive emission-line images. The method is based on the skewness of the pixel histogram of the residual images. Specifically, we exploit a transition in the skewness of the signal in the continuum-subtracted image, which appears when the image changes from being under-subtracted to over-subtracted. Tests on one-dimensional artificial images demonstrate that the transition identifies the optimal scaling factor μ to be used on the broad-band image IB in order to produce the optimal line-emission im…

The Orthogonally Aligned Dark Halo of an Edge-on Lensing Galaxy in the Hubble Frontier Fields: A Challenge for Modified Gravity

We examine a well resolved 8 arcsec lensed image that is symmetrically bent in the middle by an edge-on lenticular galaxy, in the Hubble Frontier Field (HFF) data of MACSJ0416.1-20403. The lengthy image is generated primarily by the large tangential shear of the cluster with a local secondary deflection by the member galaxy out to a limiting radius of about 18 kpc. The lensing lenticular galaxy is also well resolved and evidently lies nearly edge-on in projection. This fortuitous combination of a long arc intersecting an edge on galaxy provides us with an opportunity to place relatively strong…

哈勃深空氢α（HDH$α$）计划：I. 发射线星系目录

The Hubble Deep Hydrogen Alpha (HDH$α$) Project: I. Catalog of Emission-line Galaxies

本研究处理GOODS-S的HST F658N深空窄带数据，构建HDH$α$发射线星系样本，并通过光谱交叉验证发布不同红移的[O III]、[O II]和LAE目录。

The Hubble Legacy Archive ACS Grism Data

A public release of slitless spectra, obtained with ACS/WFC and the G800L grism, is presented. Spectra were automatically extracted in a uniform way from 153 archival fields (or "associations") distributed across the two Galactic caps, covering all observations to 2008. The ACS G800L grism provides a wavelength range of 0.55-1.00 μ$m, with a dispersion of $40 \ Å/ pixel$ and a resolution of $\sim 80\ Å$ for point-like sources. The ACS G800L images and matched direct images were reduced with an automatic pipeline that handles all steps from archive retrieval, alignment and astrometric calibrati…

The Hubble Space Telescope Wide Field Camera 3 Early Release Science data: Panchromatic Faint Object Counts for 0.2-2 microns wavelength

We describe the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) Early Release Science (ERS) observations in the Great Observatories Origins Deep Survey (GOODS) South field. The new WFC3 ERS data provide calibrated, drizzled mosaics in the UV filters F225W, F275W, and F336W, as well as in the near-IR filters F098M (Ys), F125W (J), and F160W (H) with 1-2 HST orbits per filter. Together with the existing HST Advanced Camera for Surveys (ACS) GOODS-South mosaics in the BViz filters, these panchromatic 10-band ERS data cover 40-50 square arcmin at 0.2-1.7 μm in wavelength at 0.07-0.15" FWHM…

Extinction and Dust Geometry in M83 HII Regions: A Hubble Space Telescope/WFC3 Study

We present HST/WFC3 narrow-band imaging of the starburst galaxy M83 targeting the hydrogen recombination lines (H$β$, H$α$ and Pa$β$), which we use to investigate the dust extinction in the HII regions. We derive extinction maps with 6 parsec spatial resolution from two combinations of hydrogen lines (H$α$/H$β$ and H$α$/Pa$β$), and show that the longer wavelengths probe larger optical depths, with $A_V$ values larger by $\gtrsim$1 mag than those derived from the shorter wavelengths. This difference leads to a factor $\gtrsim$2 discrepancy in the extinction-corrected H$α$ luminosity, a signific…

The 3D-HST Survey: Hubble Space Telescope WFC3/G141 grism spectra, redshifts, and emission line measurements for $\sim 100,000$ galaxies

We present reduced data and data products from the 3D-HST survey, a 248-orbit HST Treasury program. The survey obtained WFC3 G141 grism spectroscopy in four of the five CANDELS fields: AEGIS, COSMOS, GOODS-S, and UDS, along with WFC3 $H_{140}$ imaging, parallel ACS G800L spectroscopy, and parallel $I_{814}$ imaging. In a previous paper (Skelton et al. 2014) we presented photometric catalogs in these four fields and in GOODS-N, the fifth CANDELS field. Here we describe and present the WFC3 G141 spectroscopic data, again augmented with data from GO-1600 in GOODS-N. The data analysis is complicat…