Search Publications
A Morphological Classification Model to Identify Unresolved PanSTARRS1 Sources: Application in the ZTF Real-time Pipeline
Miller, A. A.; Tachibana, Yutaro
In the era of large photometric surveys, the importance of automated and accurate classification is rapidly increasing. Specifically, the separation of resolved and unresolved sources in astronomical imaging is a critical initial step for a wide array of studies, ranging from Galactic science to large scale structure and cosmology. Here, we presen…
The James Webb Space Telescope North Ecliptic Pole Time-domain Field. I. Field Selection of a JWST Community Field for Time-domain Studies
Windhorst, Rogier A.; Jansen, Rolf A.
We describe the selection of the James Webb Space Telescope (JWST) North Ecliptic Pole (NEP) Time-domain Field (TDF), a ≳14‧ diameter field located within JWST’s northern continuous viewing zone (CVZ) and centered at (R.A., decl.)J2000 = (17:22:47.896, +65:49:21.54). We demonstrate that this is the only region in the sky where JWST can …
Isochrone Fitting of Hubble Photometry in UV-VIS-IR Bands
Paust, Nathaniel E. Q.; Barker, Hallie
We present new isochrone fits to color-magnitude diagrams from Hubble Space Telescope Wide Field Camera 3 and Advanced Camera for Surveys photometry of the globular clusters M13 and M80 in five bands from the ultraviolet to near-infrared. Isochrone fits to the photometry using the Dartmouth Stellar Evolution Program (DSEP), the PAdova and TRieste …
Ultra-deep Large Binocular Camera U-band Imaging of the GOODS-North Field: Depth Versus Resolution
Fontana, Adriano; Grazian, Andrea; Rutkowski, Michael J. +13 more
We present a study of the trade-off between depth and resolution using a large number of U-band imaging observations in the GOODS-North field from the Large Binocular Camera (LBC) on the Large Binocular Telescope (LBT). Having acquired over 30 hr of data (315 images with 5-6 minutes exposures), we generated multiple image mosaics, starting with th…
Linear: A Novel Algorithm for Reconstructing Slitless Spectroscopy from HST/WFC3
Casertano, S.; Ryan, R. E., Jr.; Pirzkal, N.
We present a grism extraction package (LINEAR) designed to reconstruct 1D spectra from a collection of slitless spectroscopic images, ideally taken at a variety of orientations, dispersion directions, and/or dither positions. Our approach is to enumerate every transformation between all direct image positions (i.e., a potential source) and the col…
iPTF Survey for Cool Transients
Fox, O. D.; Cenko, S. B.; Sollerman, J. +25 more
We performed a wide-area (2000 deg2) g and I band experiment as part of a two month extension to the Intermediate Palomar Transient Factory. We discovered 36 extragalactic transients including iPTF17lf, a highly reddened local SN Ia, iPTF17bkj, a new member of the rare class of transitional Ibn/IIn supernovae, and iPTF17be, a candidate …
Complete IRAC Mapping of the CFHTLS-DEEP, MUSYC, and NMBS-II Fields
Muzzin, Adam; van Dokkum, Pieter; Bezanson, Rachel +19 more
The IRAC mapping of the NMBS-II fields program is an imaging survey at 3.6 and 4.5 µm with the Spitzer Infrared Array Camera (IRAC). The observations cover three Canada-France-Hawaii Telescope Legacy Survey Deep (CFHTLS-D) fields, including one also imaged by AEGIS, and two MUSYC fields. These are then combined with archival data from all pr…
Is the Cometary Nucleus-extraction Technique Reliable?
Li, Jian-Yang; Hui, Man-To
We investigated the reliability of the cometary nucleus-extraction technique, and found the answer to this question: it depends. Our experiment reveals that, given an optically thin coma, generally, the smaller the signal ratio of nucleus to coma, the less reliable the cometary nucleus-extraction technique is. We strongly suggest the technique onl…
A Binary Offset Effect in CCD Readout and Its Impact on Astronomical Data
Aldering, G.; Perlmutter, S.; Gangler, E. +5 more
We have discovered an anomalous behavior of CCD readout electronics that affects their use in many astronomical applications. An offset in the digitization of the CCD output voltage that depends on the binary encoding of one pixel is added to pixels that are read out one, two, and/or three pixels later. One result of this effect is the introductio…