Head-to-Toe Measurement of El Gordo: Improved Analysis of the Galaxy Cluster ACT-CL J0102–4915 with New Wide-field Hubble Space Telescope Imaging Data

Abstract We present an improved weak-lensing (WL) study of the high-z (z = 0.87) merging galaxy cluster ACT-CL J0102–4915 (“El Gordo”) based on new wide-field Hubble Space Telescope imaging data. The new imaging data cover the ∼3.5 × ∼3.5 Mpc region centered on the cluster and enable us to detect WL signals beyond the virial radius, which was not possible in previous studies. We confirm the binary mass structure consisting of the northwestern (NW) and southeastern (SE) subclusters and the ∼2σ dissociation between the SE mass peak and the X-ray cool core. We obtain the mass estimates of the subclusters by simultaneously fitting two Navarro–Frenk–White (NFW) halos without employing mass–concentration relations. The masses are M 200 c NW = 9.9 − 2.2 + 2.1 × 1014 and M 200 c SE = 6.5 − 1.4 + 1.9 × 1014 M ⊙ for the NW and SE subclusters, respectively. The mass ratio is consistent with our previous WL study but significantly different from the previous strong-lensing results. This discrepancy is attributed to the use of extrapolation in strong-lensing studies because the SE component possesses a higher concentration. By superposing the two best-fit NFW halos, we determine the total mass of El Gordo to be M 200 c = 2.13 − 0.23 + 0.25 × 1015 M ⊙, which is ∼23% lower than our previous WL result [M 200c = (2.76 ± 0.51) × 1015 M ⊙]. Our updated mass is a more direct measurement, since we are not extrapolating to R 200c as in all previous studies. The new mass is compatible with the current ΛCDM cosmology.

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ARES V: No Evidence For Molecular Absorption in the HST WFC3 Spectrum of GJ 1132 b

10.5194/epsc2021-191 ◽

2021 ◽

Author(s):

Lorenzo V. Mugnai ◽

Darius Modirrousta-Galia ◽

Billy Edwards ◽

Keyword(s):

Transmission Spectrum ◽

Hubble Space Telescope ◽

Wide Field ◽

Transmission Spectra ◽

Molecular Signatures ◽

Molecular Absorption ◽

Space Telescope ◽

James Webb Space Telescope ◽

Planetary Transmission ◽

Best Fit

We present a study on the spatially scanned spectroscopic observations of the transit of GJ 1132 b, a warm (~500 K) Super-Earth (1.13 Re) that was obtained with the G141 grism (1.125 - 1.650 micron) of the Wide Field Camera 3 (WFC3) onboard the Hubble Space Telescope. We used the publicly available Iraclis pipeline to extract the planetary transmission spectra from the five visits and produce a precise transmission spectrum. We analysed the spectrum using the TauREx3 atmospheric retrieval code with which we show that the measurements do not contain molecular signatures in the investigated wavelength range and are best-fit with a flat-line model. Our results suggest that the planet does not have a clear primordial, hydrogen-dominated atmosphere. Instead, GJ 1132 b could have a cloudy hydrogen-dominated envelope, a very enriched secondary atmosphere, be airless, or have a tenuous atmosphere that has not been detected. Due to the narrow wavelength coverage of WFC3, these scenarios cannot be distinguished yet but the James Webb Space Telescope may be capable of detecting atmospheric features, although several observations may be required to provide useful constraints

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PROBING THE CLUSTER MASS DISTRIBUTION USING SUBARU WEAK LENSING DATA

Modern Physics Letters A ◽

10.1142/s0217732307025340 ◽

2007 ◽

Vol 22 (25n28) ◽

pp. 2099-2106 ◽

Cited By ~ 13

Author(s):

KEIICHI UMETSU ◽

MASAHIRO TAKADA ◽

TOM BROADHURST

Keyword(s):

Mass Distribution ◽

Galaxy Cluster ◽

Entropy Method ◽

Weak Lensing ◽

Wide Field ◽

Imaging Data ◽

The Galaxy ◽

Dimensional Reconstruction ◽

Mass Profile ◽

Good Agreement

We present results from a weak lensing analysis of the galaxy cluster A1689 (z = 0.183) based on deep wide-field imaging data taken with Suprime-Cam on Subaru telescope. A maximum entropy method has been used to reconstruct directly the projected mass distribution of A1689 from combined lensing distortion and magnification measurements of red background galaxies. The resulting mass distribution is clearly concentrated around the cD galaxy, and mass and light in the cluster are similarly distributed in terms of shape and orientation. The azimuthally-averaged mass profile from the two-dimensional reconstruction is in good agreement with the earlier results from the Subaru one-dimensional analysis of the weak lensing data, supporting the assumption of quasi-circular symmetry in the projected mass distribution of the cluster.

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HUBBLE SPACE TELESCOPE OBSERVATIONS OF A SPECTACULAR NEW STRONG-LENSING GALAXY CLUSTER: MACS J1149.5+2223 AT z = 0.544

The Astrophysical Journal ◽

10.1088/0004-637x/707/2/l163 ◽

2009 ◽

Vol 707 (2) ◽

pp. L163-L168 ◽

Cited By ~ 89

Author(s):

Graham P. Smith ◽

Harald Ebeling ◽

Marceau Limousin ◽

Jean-Paul Kneib ◽

A. M. Swinbank ◽

...

Keyword(s):

Hubble Space Telescope ◽

Galaxy Cluster ◽

Space Telescope ◽

Strong Lensing

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Characterising the Hot Jupiters WASP-127\,b, WASP-79\,b and WASP-62\,b with HST

10.5194/epsc2020-834 ◽

2020 ◽

Author(s):

Nour Skaf

Keyword(s):

Hubble Space Telescope ◽

Wide Field ◽

Space Telescope ◽

Hot Jupiters ◽

James Webb Space Telescope ◽

Cloudy Atmosphere ◽

Iron Hydride ◽

Short Period ◽

And Migration ◽

Best Fit

We would like to present the atmospheric characterisation of three large, gaseous planets: WASP-127b, WASP-79b and WASP-62b. We analysed spectroscopic data obtained with the G141 grism (1.088 - 1.68 um) of the Wide Field Camera 3 (WFC3) onboard the Hubble Space Telescope (HST) using the Iraclis pipeline and the TauREx3 retrieval code, both of which are publicly available. For WASP-127b, which is the least dense planet discovered so far and is located in the short-period Neptune desert, our retrieval results found strong water absorption corresponding to an abundance of log(H$_2$O) = -2.71$^{+0.78}_{-1.05}$, and absorption compatible with an iron hydride abundance of log(FeH)=$-5.25^{+0.88}_{-1.10}$, with an extended cloudy atmosphere. We also detected water vapour in the atmospheres of WASP-79b and WASP-62b, with best-fit models indicating the presence of iron hydride, too. We used the Atmospheric Detectability Index (ADI) as well as Bayesian log evidence to quantify the strength of the detection and compared our results to the hot Jupiter population study by Tsiaras et al 2018. While all the planets studied here are suitable targets for characterisation with upcoming facilities such as the James Webb Space Telescope (JWST) and Ariel, WASP-127b is of particular interest due to its low density, and a thorough atmospheric study would develop our understanding of planet formation and migration.&#160;

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Examining the emission and transmission spectra of WASP-79b with retrieval

10.5194/epsc2021-830 ◽

2021 ◽

Author(s):

Michelle Bieger ◽

Quentin Changeat

Keyword(s):

Hubble Space Telescope ◽

Emission Spectra ◽

Temperature Structure ◽

Wide Field ◽

Transmission Spectra ◽

Analysis Pipeline ◽

Confidence Levels ◽

Iron Hydride ◽

Best Fit ◽

Data Analysis Pipeline

Retrieval tools provide a way of determining an exoplanet atmosphere's temperature structure and composition with an observed planetary spectrum, working backwards to determine the chemistry and temperature by iteratively comparing synthetic spectra that have been constructed via a forward model to the observed spectra and determining a best-fit result (Barstow and Heng, 2020). This talk will be presenting the emission and reanalysed transmission spectrum and retrieval analysis of WASP-79b, an inflated hot Jupiter first detected by Smalley et al. (2012). Previous transmission spectra of WASP-79b has been analysed in Sozten et al. (2020), Skaf et al. (2020), and Rathcke et al. (2021); all studies agreeing on detections of H2O with various confidence levels, with the latter finding moderate evidence of an H- bound-free opacity compared to iron hydride abundance found by the other studies. Using the publicly available \verb+Iraclis+ data analysis pipeline and the Bayesian atmospheric retrieval framework TauREx 3, we will be adding to the global picture of this planet by examining the Hubble Space Telescope emission spectra as captured by the Wide Field Camera 3 G141 grism (PI: David Sing, proposal ID: 14767).&#160;

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Wide Field Camera 3 instrument optical design for the Hubble Space Telescope

10.1117/12.550893 ◽

2004 ◽

Cited By ~ 1

Author(s):

Jennifer A. Turner-Valle ◽

Joseph Sullivan ◽

John E. Mentzell ◽

Robert A. Woodruff

Keyword(s):

Hubble Space Telescope ◽

Optical Design ◽

Wide Field ◽

Space Telescope

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Hubble Space Telescope observations of Europa in and out of eclipse

International Journal of Astrobiology ◽

10.1017/s1473550410000285 ◽

2010 ◽

Vol 9 (4) ◽

pp. 265-271 ◽

Cited By ~ 3

Author(s):

W.B. Sparks ◽

M. McGrath ◽

K. Hand ◽

H.C. Ford ◽

P. Geissler ◽

...

Keyword(s):

Hubble Space Telescope ◽

Broad Band ◽

Line Emission ◽

Optical Emission ◽

High Energy ◽

High Energy Particle ◽

Wide Field ◽

Particle Radiation ◽

Space Telescope ◽

Solar Blind

AbstractEuropa is a prime target for astrobiology and has been prioritized as the next target for a National Aeronautics and Space Administration flagship mission. It is important, therefore, that we advance our understanding of Europa, its ocean and physical environment as much as possible. Here, we describe observations of Europa obtained during its orbital eclipse by Jupiter using the Hubble Space Telescope. We obtained Advanced Camera for Surveys Solar Blind Channel far ultraviolet low-resolution spectra that show oxygen line emission both in and out of eclipse. We also used the Wide-Field and Planetary Camera-2 and searched for broad-band optical emission from fluorescence of the surface material, arising from the very high level of incident energetic particle radiation on ices and potentially organic substances. The high-energy particle radiation at the surface of Europa is extremely intense and is responsible for the production of a tenuous oxygen atmosphere and associated FUV line emission. Approximately 50% of the oxygen emission lasts at least a few hours into the eclipse. We discuss the detection limits of the optical emission, which allow us to estimate the fraction of incident energy reradiated at optical wavelengths, through electron-excited emission, Cherenkov radiation in the ice and fluorescent processes.

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Life in Low Density Environments – Field Galaxies from z=1.0 to the Present

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315010108 ◽

2015 ◽

Vol 11 (S319) ◽

pp. 127-127

Author(s):

Inger Jørgensen ◽

Scott Fisher ◽

Charity Woodrum ◽

Teiler Kwan ◽

Jacob Bieker

Keyword(s):

Hubble Space Telescope ◽

Galaxy Cluster ◽

Stellar Populations ◽

Low Density ◽

Space Telescope ◽

Cluster Galaxies ◽

Preliminary Results ◽

Spectroscopic Observations ◽

Future Work

AbstractWe present results on the stellar populations of bulge-dominated field galaxies at redshifts up to ≈1.0. The sample consists of non-cluster galaxies observed as part of the spectroscopic observations for the Gemini/HST Galaxy Cluster Project (GCP). Our preliminary results show that the bulge-dominated field galaxies contain younger stellar populations than cluster galaxies at similar redshifts. Future work will include photometry from Hubble Space Telescope and will be aimed at establishing the evolution of the sizes and the mass-to-light ratios for the field galaxies.

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