| 1. |
- Rubin, D., et al.
(författare)
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The Discovery of a Gravitationally Lensed Supernova Ia at Redshift 2.22
- 2018
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 866:1
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Tidskriftsartikel (refereegranskat)abstract
- We present the discovery and measurements of a gravitationally lensed supernova (SN) behind the galaxy cluster MOO J1014+0038. Based on multi-band Hubble Space Telescope and Very Large Telescope (VLT) photometry of the supernova, and VLT spectroscopy of the host galaxy, we find a 97.5% probability that this SN is a SN Ia, and a 2.5% chance of a CC SN. Our typing algorithm combines the shape and color of the light curve with the expected rates of each SN type in the host galaxy. With a redshift of 2.2216, this is the highest redshift SN. Ia discovered with a spectroscopic host-galaxy redshift. A further distinguishing feature is that the lensing cluster, at redshift 1.23, is the most distant to date to have an amplified SN. The SN lies in the middle of the color and light-curve shape distributions found at lower redshift, disfavoring strong evolution to z = 2.22. We estimate an amplification due to gravitational lensing of 2.8(-0.5)(+0.6) (1.10 +/- 0.23 mag)-compatible with the value estimated from the weak-lensing-derived mass and the mass-concentration relation from Lambda CDM simulations-making it the most amplified SN Ia discovered behind a galaxy cluster.
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| 2. |
- Anctil, Annick, et al.
(författare)
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Status report on emerging photovoltaics
- 2023
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Ingår i: JOURNAL OF PHOTONICS FOR ENERGY. - : SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS. - 1947-7988. ; 13:4
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Tidskriftsartikel (refereegranskat)abstract
- This report provides a snapshot of emerging photovoltaic (PV) technologies. It consists of concise contributions from experts in a wide range of fields including silicon, thin film, III-V, perovskite, organic, and dye-sensitized PVs. Strategies for exceeding the detailed balance limit and for light managing are presented, followed by a section detailing key applications and commercialization pathways. A section on sustainability then discusses the need for minimization of the environmental footprint in PV manufacturing and recycling. The report concludes with a perspective based on broad survey questions presented to the contributing authors regarding the needs and future evolution of PV.(c) 2023 Society of Photo-Optical Instrumentation Engineers (SPIE)
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| 4. |
- Berry, Teeara, et al.
(författare)
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The ALK(F1174L) mutation potentiates the oncogenic activity of MYCN in neuroblastoma
- 2012
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Ingår i: Cancer Cell. - : Elsevier BV. - 1535-6108 .- 1878-3686. ; 22:1, s. 117-130
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Tidskriftsartikel (refereegranskat)abstract
- The ALK(F1174L) mutation is associated with intrinsic and acquired resistance to crizotinib and cosegregates with MYCN in neuroblastoma. In this study, we generated a mouse model overexpressing ALK(F1174L) in the neural crest. Compared to ALKF1174L and MYCN alone, co-expression of these two oncogenes led to the development of neuroblastomas with earlier onset, higher penetrance, and enhanced lethality. ALK(F1174L)/MYCN tumors exhibited increased MYCN dosage due to ALK(F1174L)-induced activation of the PI3K/AKT/mTOR and MAPK pathways, coupled with suppression of MYCN pro-apoptotic effects. Combined treatment with the ATP-competitive mTOR inhibitor Torin2 overcame the resistance of ALK(F1174L)/MYCN tumors to crizotinib. Our findings demonstrate a pathogenic role for ALK(F1174L) in neuroblastomas overexpressing MYCN and suggest a strategy for improving targeted therapy for ALK-positive neuroblastoma.
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| 5. |
- Hayden, Brian, et al.
(författare)
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The HST See Change Program. I. Survey Design, Pipeline, and Supernova Discoveries
- 2021
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 912:2
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Tidskriftsartikel (refereegranskat)abstract
- The See Change survey was designed to make z > 1 cosmological measurements by efficiently discovering high-redshift Type Ia supernovae (SNe Ia) and improving cluster mass measurements through weak lensing. This survey observed twelve galaxy clusters with the Hubble Space Telescope (HST) spanning the redshift range z = 1.13-1.75, discovering 57 likely transients and 27 likely SNe Ia at z similar to 0.8-2.3. As in similar previous surveys, this proved to be a highly efficient use of HST for supernova observations; the See Change survey additionally tested the feasibility of maintaining, or further increasing, the efficiency at yet higher redshifts, where we have less detailed information on the expected cluster masses and star formation rates. We find that the resulting number of SNe Ia per orbit is a factor of similar to 8 higher than for a field search, and 45% of our orbits contained an active SN Ia within 22 rest-frame days of peak, with one of the clusters by itself yielding 6 of the SNe Ia. We present the survey design, pipeline, and supernova discoveries. Novel features include fully blinded supernova searches, the first random forest candidate classifier for undersampled IR data (with a 50% detection threshold within 0.05 mag of human searchers), real-time forward-modeling photometry of candidates, and semi-automated photometric classifications and follow-up forecasts. We also describe the spectroscopic follow-up, instrumental in measuring host galaxy redshifts. The cosmology analysis of our sample will be presented in a companion paper.
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| 6. |
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| 8. |
- Martz, Dale, et al.
(författare)
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Large area high efficiency broad bandwidth 800 nm dielectric gratings for high energy laser pulse compression
- 2009
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Ingår i: Optics Express. - : Optical Society of America. - 1094-4087. ; 17:26, s. 23809-23816
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Tidskriftsartikel (refereegranskat)abstract
- We have demonstrated broad bandwidth large area (229 mm x 114 mm) multilayer dielectric diffraction gratings for the efficient compression of high energy 800 nm laser pulses at high average power. The gratings are etched in the top layers of an aperiodic (Nb0.5Ta0.5)2O5-SiO2 multilayer coating deposited by ion beam sputtering. The mean efficiency of the grating across the area is better than 97% at the center wavelength and remains above 96% at wavelengths between 820 nm and 780 nm. The gratings were used to compress 5.5 J pulses from a Ti:sapphire laser with an efficiency above 80 percent.
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| 9. |
- Menoni, C. S., et al.
(författare)
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Nanoscale resolution microscopy and ablation with extreme ultraviolet lasers
- 2007
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Ingår i: 2007 IEEE LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2. - 9781424409242 ; , s. 488-489
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Konferensbidrag (refereegranskat)abstract
- We obtain a spatial resolution down to 38 run with full field imaging and laser-ablation systems that exploit the short wavelength and high brightness output from compact extreme ultraviolet lasers in combination with zone plate optics.
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| 10. |
- Rocca, J. J., et al.
(författare)
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Compact Soft X-ray Lasers for Imaging, Material Processing, and Characterization at the Nanoscale
- 2007
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Ingår i: 32nd IEEE/CPMT International Electronic Manufacturing Technology Symposium. - 9781424413355 ; , s. 72-73
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Konferensbidrag (refereegranskat)abstract
- As manufacturing of devices advances into the nanoscale, critical feature sizes have rapidly shrunk to below the wavelength of visible light. These advances in nanotechnology have created a need to develop better ways of accessing the nanoworld. The extreme ultraviolet (EUV)/ soft x-ray (SXR) region of the spectrum provides an opportunity to use coherent light at wavelengths that are 10- to 100-times shorter than visible light, at 1 to 100 nm. Given the diffraction limit in imaging resolution, these wavelengths allow us to "see" smaller features and "write" smaller patterns than would be possible with visible light. We have developed compact laser-pumped and discharge-pumped lasers operating at wavelengths of λ=13.2 nm [1] and λ=46.9 nm [2] respectively, and have used them in the demonstration of nanoscale full field imaging [3,4], nanopatterning [5], and nanoscale laser ablation [6]. The high brightness and short wavelength output from these lasers when combined with specialized EUV/SXR optics, offer unique opportunities for the implementation of table-top imaging, patterning and metrology tools with superior spatial resolution for applications in nanoscience and nanotechnology. Using these new compact short wavelength lasers we have built two microscopes, using λ=46.9 nm or λ=l 3.2 nm laser illumination. The compact λ=46.9 nm microscope (Fig. 1a and lb) condenses the light using a multilayer coated Schwarzschild mirror, and images the test object using a diffractive zone plate lens. The spatial resolution of this microscopes was assessed by imaging test samples consisting of dense line gratings of half-periods ranging from 200 down to 35 nm. Figure 2(a) and (b) show images of a 100 nm and 70 nm half-period gratings obtained with the λ =46.9 nm microscope. The lineout in the image of the 70 nm lines shows a modulation of ∼30% indicating that the features are fully resolved according to the Rayleigh criterion. By rearranging the optics, the λ=46.9 nm microscope can also image surfaces. An image of fully resolved dense metal lines, with half-period of 170 nm, patterned on the silicon wafer is shown in Figure 2 (c). The shorter wavelength λ= 3.2 nm microscope uses all zone plate optics to render images of transmissive test patterns with increased spatial resolution . An image of fully resolved 50 nm half-period dense lines acquired with a 20 seconds exposure is shown in Figure 2(d). From images like this one, the spatial resolution of the λ=13.2 nm table-top microscope was determined to be better than 38 nm [3]. The high coherence of these short wavelength lasers also allows for the printing of arrays of nanoscale features using interferometric lithography. We have demonstrated combined a λ=46.9 nm capillary discharge laser and a Lloyd's mirror to print arrays of cone-shaped nano-dots with ∼ 58 nm FWHM diameter (Fig 3a) [5]. The same arrangement was used to print arrays of nano-holes 120 nm FWHM and 100 nm in depth over areas in excess of 500 × 500 μm2 in different photoresists using exposure times as short as 80 s. Larger area patterns can be readily printed using precision translation stages and multiple exposures by overlay superposition. The ability to focus SXL laser light into near diffraction-limited spots also opens the possibility to develop new types of nanoprobes. We have demonstrated ablation of sub-100 nm diameter holes by directly focusing the output of a λ=46.9 nm laser onto a sample with a zone plate lens. Figure 3(b) shows an AFM image of a 82 nm diameter crater obtained ablating a 500 nm thick PMMA layer with a single laser shot. The holes were observed to have very clean walls and high reproducibility. We have recently added the capability to spectroscopically analyze the light emitted from the plasma created during the ablation, opening the possibility to develop analytic nanoprobles. All of these results illustrate the capabilities of compact short wavelength lasers for nanotechnology applications.
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