| 1. |
- Bhowal, S., et al.
(författare)
-
Development of collective structures over noncollective excitations in Nd-139
- 2011
-
Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 84:2
-
Tidskriftsartikel (refereegranskat)abstract
- High-spin states in Nd-139 were investigated using the reaction Zr-96(Ca-48,5n) at a beam energy of 195 MeV and gamma-ray coincidences were acquired with the Euroball spectrometer. Apart from several dipole bands at medium excitation energy, three quadrupole bands have been observed at high spin. Linking transitions connecting two of the high-spin bands to low-energy states have been observed. Calculations based on the cranked-Nilsson-Strutinsky formalism have been used to assign configurations for the high-spin quadrupole bands.
|
|
| 2. |
- Petrache, C. M., et al.
(författare)
-
Triaxiality at high spins in Nd nuclei
- 2006
-
Ingår i: Physica Scripta. - 0031-8949. ; T125, s. 212-213
-
Tidskriftsartikel (refereegranskat)abstract
- The level structure of Nd-140(80) has been established up to spin 48 by in-beam gamma-ray spectroscopy using the Zr-96(Ca-48, 4n) reaction. High-fold gamma-ray coincidences were measured with the EUROBALL spectrometer. Twelve new rotational bands have been discovered at high spins, showing the change from a spherical single-particle behaviour at low spins to a deformed regime with stable triaxiality at high spins. Possible configurations are assigned to the observed bands on the basis of configuration-dependent cranked Nilsson-Strutinsky calculations.
|
|
| 3. |
- Andrews, Jennifer E., et al.
(författare)
-
SN 2017gmr : An Energetic Type II-P Supernova with Asymmetries
- 2019
-
Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 885:1
-
Tidskriftsartikel (refereegranskat)abstract
- We present high-cadence UV, optical, and near-infrared data on the luminous Type II-P supernova SN;2017gmr from hours after discovery through the first 180 days. SN;2017gmr does not show signs of narrow, high-ionization emission lines in the early optical spectra, yet the optical light-curve evolution suggests that an extra energy source from circumstellar medium (CSM) interaction must be present for at least 2 days after explosion. Modeling of the early light curve indicates a ?500 R progenitor radius, consistent with a rather compact red supergiant, and late-time luminosities indicate that up to 0.130;;0.026 M of Ni-56 are present, if the light curve is solely powered by radioactive decay, although the Ni-56 mass may be lower if CSM interaction contributes to the post-plateau luminosity. Prominent multipeaked emission lines of H? and [O i] emerge after day 154, as a result of either an asymmetric explosion or asymmetries in the CSM. The lack of narrow lines within the first 2 days of explosion in the likely presence of CSM interaction may be an example of close, dense, asymmetric CSM that is quickly enveloped by the spherical supernova ejecta.
|
|
| 4. |
- Neusser, A, et al.
(författare)
-
Superdeformed band at very high spin in Nd-140
- 2004
-
Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 70:6
-
Tidskriftsartikel (refereegranskat)abstract
- A new high-spin superdeformed band has been discovered in Nd-140(60)80. It was populated in the Zr-96(Ca-48,4n) reaction and investigated using the EUROBALL gamma-ray spectrometer array. The band is observed in the approximate spin range of I=36 to 66. It is associated with shell gaps around Z=60 and at N=80 at large deformation. These gaps produce a pronounced minimum in the calculated total Routhian surfaces at a quadrupole deformation of epsilon(2)=0.45. The new band which lies between the high-deformation bands in the Aapproximate to130 region and the superdeformed bands in Aapproximate to150 nuclei provides insight into the development of the deformation between these two regions. Two possible configurations are suggested involving four neutrons of i(13/2) origin (nu6(4)) and either six protons of h(11/2)/h(9/2) origin (pi5(6)) or five protons of h(11/2)/h(9/2) and one of i(13/2) origin (pi5(5)6(1)).
|
|
| 5. |
|
|
| 6. |
- Dastidar, Raya, et al.
(författare)
-
SN 2015ba : a Type IIP supernova with a long plateau
- 2018
-
Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 479:2, s. 2421-2442
-
Tidskriftsartikel (refereegranskat)abstract
- We present optical photometry and spectroscopy from about a week after explosion to similar to 272 d of an atypical Type IIP supernova, SN 2015ba, which exploded in the edge-on galaxy IC 1029. SN 2015ba is a luminous event with an absolute V-band magnitude of -17.1 +/- 0.2 mag at 50 d since explosion and has a long plateau lasting for similar to 123 d. The distance to the SN is estimated to be 34.8 +/- 0.7 Mpc using the expanding photosphere and standard candle methods. High-velocity H Balmer components constant with time are observed in the late-plateau phase spectra of SN 2015ba, which suggests a possible role of circumstellar interaction at these phases. Both hydrodynamical and analytical modelling suggest a massive progenitor of SN 2015ba with a pre-explosion mass of 24-26 M-circle dot. However, the nebular spectra of SN 2015ba exhibit insignificant levels of oxygen, which is otherwise expected from a massive progenitor. This might be suggestive of the non-monotonical link between O-core masses and the zero-age main sequence mass of pre-supernova stars and/or uncertainties in the mixing scenario in the ejecta of supernovae.
|
|
| 7. |
- Dastidar, R., et al.
(författare)
-
The optical properties of three Type II supernovae : 2014cx, 2014cy, and 2015cz
- 2021
-
Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 504:1, s. 1009-1028
-
Tidskriftsartikel (refereegranskat)abstract
- We present the photometric and spectroscopic analysis of three Type II supernovae (SNe): 2014cx, 2014cy, and 2015cz. SN 2014cx is a conventional Type IIP with shallow slope (0.2 mag/50 d) and an atypical short plateau (∼86 d). SNe 2014cy and 2015cz show relatively large decline rates (0.88 and 1.64 mag/50 d, respectively) at early times before settling to the plateau phase, unlike the canonical Type IIP/L SN light curves. All of them are normal luminosity SN II with an absolute magnitude at mid-plateau of M50V,14cx=−16.6±0.4mag, M50V,14cy=−16.5±0.2mag, and M50V,15cz=−17.4±0.3mag. A relatively broad range of 56Ni masses is ejected in these explosions (0.027–0.070 M⊙). The spectra shows the classical evolution of SNe II, dominated by a blue continuum with broad H lines at early phases and narrower metal lines with P Cygni profiles during the plateau. High-velocity H i features are identified in the plateau spectra of SN 2014cx at 11 600 kms −1, possibly a sign of ejecta-circumstellar interaction. The spectra of SN 2014cy exhibit strong absorption profile of H i similar to normal luminosity events whereas strong metal lines akin to sub-luminous SNe. The analytical modelling of the bolometric light curve of the three events yields similar progenitor radii within errors (478, 507, and 660 R ⊙ for SNe 2014cx, 2014cy, and 2015cz, respectively), a range of ejecta masses (15.0, 22.2, and 20.6 M ⊙ for SNe 2014cx, 2014cy, and 2015cz), and a modest range of explosion energies (3.3–7.2 foe where 1 foe=10 51erg).
|
|
| 8. |
- Gangopadhyay, S., et al.
(författare)
-
C-60 submonolayers on the Si(111)-(7 x 7) surface: Does a mixture of physisorbed and chemisorbed states exist?
- 2009
-
Ingår i: Surface Science. - : Elsevier BV. - 0039-6028. ; 603:18, s. 2896-2901
-
Tidskriftsartikel (refereegranskat)abstract
- We have carried out a combined X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy(UPS), and scanning tunnelling microscopy (STM) study of the C-60-Si(1 1 1) interaction where the XPS/UPS spectrometer and STM are integrated on a single UHV system. This enables a direct comparison of the XPS/UPS spectra with the STM data and eliminates any uncertainty in C-60 coverage measurements. X-ray standing wave measurements and density functional theory calculations have been used to support and interpret the results of the XPS/UPS/STM experiments. Our data conclusively rule out models of C-60 adsorption which involve a mixture of physisorbed and chemisorbed molecules [K. Sakamoto, et al., Phys. Rev. B 60 (1999) 2579]. Instead, we find that all molecules, up to 1 monolayer coverage, bond to the surface via Si-C bonds which are predominantly of covalent character. (C) 2009 Elsevier B.V. All rights reserved.
|
|
| 9. |
- Calis, T., et al.
(författare)
-
Does Microfinance Make Households More Resilient to Shocks? Evidence From the Cyclone Phailin in India
- 2017
-
Ingår i: Journal of International Development. - : Wiley. - 0954-1748. ; 29:7, s. 1011-1015
-
Tidskriftsartikel (refereegranskat)abstract
- This research note examines the relevance of microfinance as a means to cope with natural disasters, using the event of the cyclone Phailin, which struck India in 2013. The results indicate that microfinance helps reduce the negative effects of extreme weather-related shocks. In light of the somewhat disappointing outcomes suggested by several recent rigorous impact studies, this research paints a more positive picture of the importance of microfinance as an insurance mechanism to deal with weather-related risks.
|
|
