scholarly journals Two- and three-dimensional wide-field weak lensing mass maps from the Hyper Suprime-Cam Subaru Strategic Program S16A data

Author(s):  
Masamune Oguri ◽  
Satoshi Miyazaki ◽  
Chiaki Hikage ◽  
Rachel Mandelbaum ◽  
Yousuke Utsumi ◽  
...  
Author(s):  
Rhythm Shimakawa ◽  
Yuichi Higuchi ◽  
Masato Shirasaki ◽  
Masayuki Tanaka ◽  
Yen-Ting Lin ◽  
...  

Abstract Subaru Strategic Program with the Hyper-Suprime Cam (HSC-SSP) has proven to be successful with its extremely-wide area coverage in past years. Taking advantages of this feature, we report initial results from exploration and research of expansive over- and under-dense structures at z = 0.3 – 1 based on the second Public Data Release where optical 5-band photometric data for ∼ eight million sources with i < 23 mag are available over ∼360 square degrees. We not only confirm known superclusters but also find candidates of titanic over- and under-dense regions out to z = 1. The mock data analysis suggests that the density peaks would involve one or more massive dark matter haloes (>1014 M⊙) of the redshift, and the density troughs tend to be empty of massive haloes over >10 comoving Mpc. Besides, the density peaks and troughs at z ≲ 0.6 are in part identified as positive and negative weak lensing signals respectively, in mean tangential shear profiles, showing a good agreement with those inferred from the full-sky weak lensing simulation. The coming extensive spectroscopic surveys will be able to resolve these colossal structures in three-dimensional space. The number density information over the entire survey field is available as grid-point data on the website of the HSC-SSP data release (https://hsc.mtk.nao.ac.jp/ssp/data-release/).


Author(s):  
E Gaztanaga ◽  
S J Schmidt ◽  
M D Schneider ◽  
J A Tyson

Abstract We test the impact of some systematic errors in weak lensing magnification measurements with the COSMOS 30-band photo-z Survey flux limited to Iauto < 25.0 using correlations of both source galaxy counts and magnitudes. Systematic obscuration effects are measured by comparing counts and magnification correlations. We use the ACS-HST catalogs to identify potential blending objects (close pairs) and perform the magnification analyses with and without blended objects. We find that blending effects start to be important (∼ 0.04 mag obscuration) at angular scales smaller than 0.1 arcmin. Extinction and other systematic obscuration effects can be as large as 0.10 mag (U-band) but are typically smaller than 0.02 mag depending on the band. After applying these corrections, we measure a 3.9σ magnification signal that is consistent for both counts and magnitudes. The corresponding projected mass profiles of galaxies at redshift z ≃ 0.6 (MI ≃ −21) is Σ = 25 ± 6M⊙h3/pc2 at 0.1 Mpc/h, consistent with NFW type profile with M200 ≃ 2 × 1012M⊙h/pc2. Tangential shear and flux-size magnification over the same lenses show similar mass profiles. We conclude that magnification from counts and fluxes using photometric redshifts has the potential to provide complementary weak lensing information in future wide field surveys once we carefully take into account systematic effects, such as obscuration and blending.


2007 ◽  
Vol 172 (1) ◽  
pp. 239-253 ◽  
Author(s):  
Richard Massey ◽  
Jason Rhodes ◽  
Alexie Leauthaud ◽  
Peter Capak ◽  
Richard Ellis ◽  
...  

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2918 ◽  
Author(s):  
Junseong Eom ◽  
Sangjun Moon

The digital in-line holographic microscope (DIHM) was developed for a 2D imaging technology and has recently been adapted to 3D imaging methods, providing new approaches to obtaining volumetric images with both a high resolution and wide field-of-view (FOV), which allows the physical limitations to be overcome. However, during the sectioning process of 3D image generation, the out-of-focus image of the object becomes a significant impediment to obtaining evident 3D features in the 2D sectioning plane of a thick biological sample. Based on phase retrieved high-resolution holographic imaging and a 3D deconvolution technique, we demonstrate that a high-resolution 3D volumetric image, which significantly reduces wave-front reconstruction and out-of-focus artifacts, can be achieved. The results show a 3D volumetric image that is more finely focused compared to a conventional 3D stacked image from 2D reconstructed images in relation to micron-size polystyrene beads, a whole blood smear, and a kidney tissue sample. We believe that this technology can be applicable for medical-grade images of smeared whole blood or an optically cleared tissue sample for mobile phytological microscopy and laser sectioning microscopy.


2021 ◽  
Author(s):  
Xuepeng Chen ◽  
Weihua Guo ◽  
Jiangcheng Feng ◽  
Yang Su ◽  
Yan Sun ◽  
...  

Abstract Located at a distance of about 300 pc, Perseus OB2 (or Per~OB2 for short) is one of the major OB associations in the solar vicinity\cite{Zeeuw99,Belikov2002}, which has blown a supershell with a diameter of about 15 degree seen in the atomic hydrogen line surveys\cite{Sancisi1974,Heiles1984,Hartmann1997}. It was long considered that stellar feedback from the Per~OB2 association had formed a superbubble that swept up the surrounding interstellar medium into the observed supershell\cite{Bally2008}. Here we report the three-dimensional structure of the Per~OB2 superbubble, based on wide-field atomic hydrogen and molecular gas (traced by CO) surveys. The measured diameter of the superbubble is roughly 330 pc. Multiple atomic hydrogen shells/loops with expansion velocities of about 10 km/s are revealed in the superbubble, suggesting a complicated evolution history of the superbubble. Furthermore, the inspections of the morphology, kinematics and timescale of the Taurus-Auriga, California, and Perseus molecular clouds shows that the cloud complex is a super molecular cloud loop circling around and co-expanding with the Per~OB2 superbubble. We conclude that the Taurus-Auriga-California-Perseus loop, the largest star-forming molecular cloud complex in the solar neighborhood, is formed from the feedback of the Per~OB2 superbubble.


Author(s):  
Takashi Hamana ◽  
Masato Shirasaki ◽  
Yen-Ting Lin

Abstract We present a weak-lensing cluster search using Hyper Suprime-Cam Subaru Strategic Program (HSC survey) first-year data. We pay special attention to the dilution effect of cluster-member and foreground galaxies on weak-lensing signals from clusters of galaxies; we adopt the globally normalized weak-lensing estimator which is least affected by cluster-member galaxies, and we select source galaxies by using photometric redshift information to mitigate the effect of foreground galaxies. We produce six samples of source galaxies with different low-z galaxy cuts, construct weak-lensing mass maps for each source sample, and search for high peaks in the mass maps that cover an effective survey area of ∼120 deg2. We combine six catalogs of high peaks into a sample of cluster candidates which contains 124 high peaks with signal-to-noise ratios greater than five. We cross-match the peak sample with the public optical cluster catalog constructed from the same HSC survey data to identify cluster counterparts of the peaks. We find that 107 out of 124 peaks have matched clusters within 5′ of peak positions. Among them, we define a subsample of 64 secure clusters that we use to examine dilution effects on our weak-lensing cluster search. We find that source samples with low-z galaxy cuts mitigate the dilution effect on weak-lensing signals of high-z clusters ($z \gtrsim 0.3$), and thus combining multiple peak catalogs from different source samples improves the efficiency of weak-lensing cluster searches.


Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 293
Author(s):  
Wenhao Du ◽  
Cheng Fei ◽  
Junliang Liu ◽  
Yongfu Li ◽  
Zhaojun Liu ◽  
...  

Optical projection tomography (OPT) is the direct optical equivalent of X-ray computed tomography (CT). To obtain a larger depth of field, traditional OPT usually decreases the numerical aperture (NA) of the objective lens to decrease the resolution of the image. So, there is a trade-off between sample size and resolution. Commercial microfluidic systems can observe a sample in flow mode. In this paper, an OPT instrument is constructed to observe samples. The OPT instrument is combined with commercial microfluidic systems to obtain a three-dimensional and time (3D + T)/four-dimensional (4D) video of the sample. “Focal plane scanning” is also used to increase the images’ depth of field. A series of two-dimensional (2D) images in different focal planes was observed and compared with images simulated using our program. Our work dynamically monitors 3D OPT images. Commercial microfluidic systems simulate blood flow, which has potential application in blood monitoring and intelligent drug delivery platforms. We design an OPT adaptor to perform OPT on a commercial wide-field inverted microscope (Olympusix81). Images in different focal planes are observed and analyzed. Using a commercial microfluidic system, a video is also acquired to record motion pictures of samples at different flow rates. To our knowledge, this is the first time an OPT setup has been combined with a microfluidic system.


1958 ◽  
Vol 36 (6) ◽  
pp. 659-671 ◽  
Author(s):  
B. W. Schumacher ◽  
E. O. Gadamer

An electron beam was fired across the field of observation of the UTIA low-density wind tunnel. Along its path gaseous fluorescence was excited and visible light emitted. The total light output per unit length of the electron beam can be assumed to be proportional to the density of the gas if suitable spectral lines are selected. A three-dimensional scan of the field would give the local density for each spot. Visual, photographic, and photometric observation is possible. Some photographs are presented along with approximate data for the light output in air. The spatial resolution of the fluorescence probe is also discussed.


2015 ◽  
Vol 40 (21) ◽  
pp. 4847 ◽  
Author(s):  
Roman Spesyvtsev ◽  
Helen A. Rendall ◽  
Kishan Dholakia

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