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3. Constraints on $w_0$ and $w_a$ of Dark Energy from High Redshift Gamma Ray Bursts

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, Kodama, Yoshiki, and Takahashi, Keitaro

Subjects
Astrophysics
Abstract

We extend the Hubble diagram up to $z = 5.6$ using 63 gamma-ray bursts (GRBs) via peak energy-peak luminosity relation (so called Yonetoku relation), and obtain constraints on cosmological parameters including dynamical dark energy parametrized by $P/\rho\equiv w(z) = w_0 + w_a \cdot z/(1+z)$. It is found that the current GRB data are consistent with the concordance model, ($\Omega_m = 0.28, \Omega_{\Lambda} = 0.72, w_0 = -1, w_a = 0$), within two sigma level. Although constraints from GRBs themselves are not so strong, they can improve the conventional constraints from SNeIa because GRBs have much higher redshifts. Further we estimate the constraints on the dark-energy parameters expected by future observations with GLAST (Gamma-ray Large Area Space Telescope) and \swift by Monte-Carlo simulation. Constraints would improve substantially with another 150 GRBs., Comment: 5 pages, 6 figures. Submitted tu MNRAS

Published
2008
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4. Gamma-Ray Bursts in $1.8 < z < 5.6$ Suggest that the Time Variation of the Dark Energy is Small

Author

Kodama, Yoshiki, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, Tsutsui, Ryo, and Nakamura, Takashi

Subjects
Astrophysics, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology
Abstract

We calibrated the peak energy-peak luminosity relation of GRBs (so called Yonetoku relation) using 33 events with the redshift $z < 1.62$ without assuming any cosmological models. The luminosity distances to GRBs are estimated from those of large amount of Type Ia supernovae with $z<1.755$. This calibrated Yonetoku relation can be used as a new cosmic distance ladder toward higher redshifts. We determined the luminosity distances of 30 GRBs in $1.8 < z < 5.6$ using the calibrated relation and plotted the likelihood contour in $(\Omega_m,\Omega_\Lambda)$ plane. We obtained $(\Omega_m, \Omega_{\Lambda})= (0.37^{+0.14}_{-0.11}, 0.63^{+0.11}_{-0.14})$ for a flat universe. Since our method is free from the circularity problem, we can say that our universe in $1.8 < z < 5.6$ is compatible with the so called concordance cosmological model derived for $z < 1.8$. This suggests that the time variation of the dark energy is small or zero up to $z\sim 6$., Comment: 4 pages, 4 figures, accepted to MNRAS

Published
2008
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5. Redshift Dependent Lag-Luminosity Relation in 565 BASTE Gamma Ray Bursts

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, and Kodama, Yoshiki

Subjects
Astrophysics
Abstract

We compared redshifts $z_Y$ from Yonetoku relation and $z_{lag}$ from the lag-luminosity relation for 565 BASTE GRBs and were surprised to find that the correlation is very low. Assuming that the luminosity is a function of both $z_Y$ and the intrinsic spectral lag $\tau_{lag}$, we found a new redshift dependent lag-luminosity relation as $L=7.5\times 10^{50}{\rm erg/s}(1+z)^{2.53}\tau_{lag}^{-0.282}$ with the correlation coefficient of 0.77 and the chance probability of $7.9\times 10^{-75}$. To check the validity of this method, we examined the other luminosity indicator, Amati relation, using $z_Y$ and the observed fluence and found the correlation coefficient of 0.92 and the chance probability of $5.2\times 10^{-106}$. Although the spectral lag is computed from two channels of BATSE, our new lag-luminosity relation suggests that a possible lag-luminosity relation in the \swift era should also depend on redshift.

Published
2007
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6. Spectral evolution of GRB 060904A observed with Swift and Suzaku -- Possibility of Inefficient Electron Acceleration

Author

Yonetoku, Daisuke, Tanabe, Sachiko, Murakami, Toshio, Emura, Naomi, Aoyama, Yuka, Kidamura, Takashi, Kodaira, Hironobu, Kodama, Yoshiki, Kozaka, Ryota, Nashimoto, Takuro, Okuno, Shinya, Yokota, Satoshi, Yoshinari, Satoru, Abe, Keiichi, Onda, Kaori, Tashiro, Makoto S., Urata, Yuji, Nakagawa, Yujin E., Sugita, Satoshi, Yamaoka, Kazutaka, Yoshida, Atsumasa, Ishimura, Takuto, Kawai, Nobuyuki, Shimokawabe, Takashi, Kinugasa, Kenzo, Kohmura, Takayoshi, Kubota, Kaori, Sugiyasu, Kei, Ueda, Yoshihiro, Masui, Kensuke, Nakazawa, Kazuhiro, Takahashi, Tadayuki, Maeno, Shouta, Sonoda, Eri, Yamauchi, Makoto, Kuwahara, Makoto, Tamagawa, Toru, Matsuura, Daisuke, Suzuki, Motoko, Barthelmy, Scott, Gehrels, Neil, and Nousek, John

Subjects
Astrophysics
Abstract

We observed an X-ray afterglow of GRB 060904A with the Swift and Suzaku satellites. We found rapid spectral softening during both the prompt tail phase and the decline phase of an X-ray flare in the BAT and XRT data. The observed spectra were fit by power-law photon indices which rapidly changed from $\Gamma = 1.51^{+0.04}_{-0.03}$ to $\Gamma = 5.30^{+0.69}_{-0.59}$ within a few hundred seconds in the prompt tail. This is one of the steepest X-ray spectra ever observed, making it quite difficult to explain by simple electron acceleration and synchrotron radiation. Then, we applied an alternative spectral fitting using a broken power-law with exponential cutoff (BPEC) model. It is valid to consider the situation that the cutoff energy is equivalent to the synchrotron frequency of the maximum energy electrons in their energy distribution. Since the spectral cutoff appears in the soft X-ray band, we conclude the electron acceleration has been inefficient in the internal shocks of GRB 060904A. These cutoff spectra suddenly disappeared at the transition time from the prompt tail phase to the shallow decay one. After that, typical afterglow spectra with the photon indices of 2.0 are continuously and preciously monitored by both XRT and Suzaku/XIS up to 1 day since the burst trigger time. We could successfully trace the temporal history of two characteristic break energies (peak energy and cutoff energy) and they show the time dependence of $\propto t^{-3} \sim t^{-4}$ while the following afterglow spectra are quite stable. This fact indicates that the emitting material of prompt tail is due to completely different dynamics from the shallow decay component. Therefore we conclude the emission sites of two distinct phenomena obviously differ from each other., Comment: 19 pages, 9 figures, accepted for publication in PASJ (Suzaku 2nd Special Issue)

Published
2007
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17. Binocular superior visual field areas associated with driving self-regulation in patients with primary open-angle glaucoma.

Author

Tomoyo Yamasaki, Kenya Yuki, Awano-Tanabe, Sachiko, Takeshi Ono, Hiroshi Murata, Kazuo Tsubota, and Asaoka, Ryo

Abstract

Background/aims The aim of our study was to investigate the associations between driving self-regulation and glaucoma severity, and between driving self-regulation and glaucomatous visual field (VF) defect patterns. Methods In 247 patients with primary open-angle glaucoma included in this prospective observational study, a battery of ophthalmic examination was performed, including visual acuity (VA) and VF. Integrated binocular VF was constructed and mean of total deviation (mTD) values in four sectors was calculated (mTDsup-peri, mTDsup-centre, mTDinf-peri and mTDinf-centre). In addition, all participants answered seven questions regarding their avoidance in driving. (1) at night, (2) in rain, (3) in fog, (4) on freeways, (5) lane changing, (6) at high speed and (7) close to the car in front. The associations between these driving behaviours and 10 variables (age, gender, best VA, worst VA, the four sectorial average TD values, years holding a driver's licence and distance driven per week) were analysed using the generalised linear model with binomial distribution, followed by the model section method using the corrected Akaike information criterion. Results As a result of the model selection, it was suggested that deterioration of mTDsup-peri was associated with (1) avoiding driving at night and (2) avoiding driving in rain. On the other hand, mTDsup-centre was related to (3) avoiding driving in fog. Conclusion Damage in visual function was related with driving behaviours in patients with glaucoma. [ABSTRACT FROM AUTHOR]

Published
2021
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21. Binocular superior visual field areas associated with driving self-regulation in patients with primary open-angle glaucoma

Author

Yamasaki, Tomoyo, Yuki, Kenya, Awano-Tanabe, Sachiko, Ono, Takeshi, Murata, Hiroshi, Tsubota, Kazuo, and Asaoka, Ryo

Abstract

Background/aimsThe aim of our study was to investigate the associations between driving self-regulation and glaucoma severity, and between driving self-regulation and glaucomatous visual field (VF) defect patterns.MethodsIn 247 patients with primary open-angle glaucoma included in this prospective observational study, a battery of ophthalmic examination was performed, including visual acuity (VA) and VF. Integrated binocular VF was constructed and mean of total deviation (mTD) values in four sectors was calculated (mTDsup-peri, mTDsup-centre, mTDinf-peri and mTDinf-centre). In addition, all participants answered seven questions regarding their avoidance in driving. (1) at night, (2) in rain, (3) in fog, (4) on freeways, (5) lane changing, (6) at high speed and (7) close to the car in front. The associations between these driving behaviours and 10 variables (age, gender, best VA, worst VA, the four sectorial average TD values, years holding a driver’s licence and distance driven per week) were analysed using the generalised linear model with binomial distribution, followed by the model section method using the corrected Akaike information criterion.ResultsAs a result of the model selection, it was suggested that deterioration of mTDsup-peri was associated with (1) avoiding driving at night and (2) avoiding driving in rain. On the other hand, mTDsup-centre was related to (3) avoiding driving in fog.ConclusionDamage in visual function was related with driving behaviours in patients with glaucoma.

Published
2021
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24. Factors associated with the occurrence of a fall in subjects with primary open-angle glaucoma.

Author

Sayaka Adachi, Kenya Yuki, Sachiko Awano-Tanabe, Takeshi Ono, Hiroshi Murata, Ryo Asaoka, Kazuo Tsubota, Adachi, Sayaka, Yuki, Kenya, Awano-Tanabe, Sachiko, Ono, Takeshi, Murata, Hiroshi, Asaoka, Ryo, and Tsubota, Kazuo

Subjects
ACCIDENTAL falls, FEAR, GLAUCOMA, HYPERTENSION, LONGITUDINAL method, RESEARCH funding, VISUAL fields, COMORBIDITY, DISEASE complications
Abstract

Background: The aim of the study is to investigate risk factors for future falls in subject with primary open angle glaucoma (POAG).Methods: All participants answered the following question at their baseline ophthalmic examination: Have you had any falls in the last year? (Yes/No). All study participants answered the same question every 12 months for 3 years. The means of total deviation values in the whole, superior peripheral, superior central, inferior central, and inferior peripheral visual fields (VF) were calculated. The relationship between these mean VF measurements, and various clinical factors against patients' future falls was analyzed using multiple linear regression.Results: Two-hundred ninety four POAG patients answered the baseline and follow-up fall questionnaires over a period of three years. Among 294 subjects, 69 patients experienced a fall during the three-year follow-up. History of falls at baseline (coefficient = 1.22), history of fear of falling at baseline (0.53), best corrected visual acuity in the worse eye (7.37), prevalence of diabetes mellitus (0.60), prevalence of systemic hypertension (0.53) were selected in the optimal model.Conclusions: Visual acuity in the worse eye, history of falls, fear of falling, diabetes mellitus, and systemic hypertension are risk factors for falling in subjects with POAG. [ABSTRACT FROM AUTHOR]

Published
2017
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26. Glaucomatous Visual Field Defect Severity and the Prevalence of Motor Vehicle Collisions in Japanese: A Hospital/Clinic-Based Cross-Sectional Study

Author

Ono, Takeshi, primary, Yuki, Kenya, additional, Asaoka, Ryo, additional, Kouyama, Keisuke, additional, Abe, Takayuki, additional, Tanabe, Sachiko, additional, Fukagawa, Kazumi, additional, Uchino, Miki, additional, Shimoyama, Masaru, additional, Ozawa, Yoko, additional, Ozeki, Naoki, additional, Shiba, Daisuke, additional, and Tsubota, Kazuo, additional

Published
2015
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27. Two types of energetic radiation associeted with thunderstorm

Author

Torii, Tatsuo, Sugita, Takeshi, Tanabe, Sachiko, Kimura, Yoshinao, Kamogawa, Masashi, Yajima, Kazuaki, and Yasuda, Hiroshi

Abstract

富士山頂で観測された雷活動に伴う環境放射線の強度上昇について報告した。, EGU General Assembly 2009

Published
2009

28. Multivariable Logistic Regression Model: A Novel Mathematical Model that Predicts Visual Field Sensitivity from Macular Ganglion Cell Complex Thickness in Glaucoma

Author

Shiba, Daisuke, primary, Hatou, Shin, additional, Ono, Takeshi, additional, Hosoda, Shingo, additional, Tanabe, Sachiko, additional, Ozeki, Naoki, additional, Yuki, Kenya, additional, Shimoyama, Masaru, additional, Fukagawa, Kazumi, additional, Shimmura, Shigeto, additional, and Tsubota, Kazuo, additional

Published
2014
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31. The association between primary open-angle glaucoma and fall: an observational study

Author

Tanabe,Sachiko, Yuki,Kenya, Ozeki,Naoki, Shiba,Daisuke, Tsubota,Kazuo, Tanabe,Sachiko, Yuki,Kenya, Ozeki,Naoki, Shiba,Daisuke, and Tsubota,Kazuo

Abstract

Sachiko Tanabe1,2*, Kenya Yuki1*, Naoki Ozeki1, Daisuke Shiba1, Kazuo Tsubota11Department of Ophthalmology, Keio University School of Medicine, Shinanomachi 35, Tokyo, Japan; 2Tanabe Eye Clinic, Kai City, Yamanashi, Japan*These authors contributed equally to this workPurpose: Falls are among the most serious public health concerns for the elderly. Information conveyed via the visual sense is relevant to postural balance and movement, and proper visual function is essential to avoid falls. Here we investigated the prevalence of injurious falls among patients with primary open-angle glaucoma (POAG) who were more than 45 years old, compared with comparably aged healthy subjects.Methods: This is a cross-sectional study. Consecutive patients who visited the Tanabe Eye Clinic, Yamanashi, Japan between January 1 and March 30, 2009 were screened for eligibility by ophthalmic examination. A total of 117 control subjects (77 men, 40 women; aged 60.2 ± 7.5 years) who were free of ocular disease and 101 POAG patients (58 men, 43 women; aged 62.3 ± 8.7 years) were consecutively enrolled. Participants answered a questionnaire on injurious fall experience during the previous 10 years. The prevalence of injurious fall in subjects with POAG versus healthy controls was examined with Fisher's exact test. Adjusted odds ratios and 95% confidence intervals were estimated with logistic regression models for the subjects with POAG (factors: age, gender, mean deviation in the better eye or worse eye).Results: The self-reported prevalence of injurious fall was 0.9% (1/117) in the control group and 6.9% (7/101) in the POAG group. The association between injurious fall and POAG was statistically significant (P = 0.026, Fisher's exact test). Within the POAG patients, the group reporting falls was significantly older and had a lower BMI, worse BCVA, and worse mean deviation in both the better and worse eye than the group reporting no falls. Worse mean deviat

Published
2012

33. Light Delivery System for Heat-Assisted Magnetic Recording

Author

Hirata, Masakazu, primary, Tanabe, Sachiko, additional, Oumi, Manabu, additional, Park, Majung, additional, Chiba, Norio, additional, Gonzaga, Leonard V., additional, Yu, Shengkai, additional, Zhang, Mingsheng, additional, and Tjiptoharsono, Febiana, additional

Published
2009
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38. Spectral Evolution of GRB060904A Observed with Swift and Suzaku- Possibility of Inefficient Electron Acceleration

Author

Yonetoku, Daisuke, primary, Tanabe, Sachiko, additional, Murakami, Toshio, additional, Emura, Naomi, additional, Aoyama, Yuka, additional, Kidamura, Takashi, additional, Kodaira, Hironobu, additional, Kodama, Yoshiki, additional, Kozaka, Ryota, additional, Nashimoto, Takuro, additional, Okuno, Shinya, additional, Yokota, Satoshi, additional, Yoshinari, Satoru, additional, Abe, Keiichi, additional, Onda, Kaori, additional, Tashiro, Makoto S., additional, Urata, Yuji, additional, Nakagawa, Yujin E., additional, Sugita, Satoshi, additional, Yamaoka, Kazutaka, additional, Yoshida, Atsumasa, additional, Ishimura, Takuto, additional, Kawai, Nobuyuki, additional, Shimokawabe, Takashi, additional, Kinugasa, Kenzo, additional, Kohmura, Takayoshi, additional, Kubota, Kaori, additional, Sugiyasu, Kei, additional, Ueda, Yoshihiro, additional, Masui, Kensuke, additional, Nakazawa, Kazuhiro, additional, Takahashi, Tadayuki, additional, Maeno, Shouta, additional, Sonoda, Eri, additional, Yamauchi, Makoto, additional, Kuwahara, Makoto, additional, Tamagawa, Toru, additional, Matsuura, Daisuke, additional, Suzuki, Motoko, additional, Barthelmy, Scott, additional, Gehrels, Neil, additional, and Nousek, John, additional

Published
2008
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39. Gradual increase of energetic radiation in associated with thunderstorm activity at the top of Mt.Fuji

Author

Torii, Tatsuo, Sugita, Takeshi, Tanabe, Sachiko, Kimura, Yoshihisa, Kamogawa, Masashi, Yajima, Kazuaki, and Yasuda, Hiroshi

Subjects
Astrophysics::High Energy Astrophysical Phenomena
Abstract

Fluctuations of energetic radiation were observed at the top of Mt.Fuji. The largest event was gradual and lasted for about 20 minutes, attributing to high-energy gamma rays having a continuous energy spectrum up to 10 MeV or more. Such fluctuations are possibly caused by the bremsstrahlung photons generated by the energetic electrons produced continuously with an intense electric field in the thundercloud.

Published
2009

40. Automated 1.3-m near-infrared telescope system triggered by gamma-ray burst

Author

Murakami, Toshio, primary, Yonetoku, Daisuke, additional, Kinoshita, Shin, additional, Masui, Hiroki, additional, Okuno, Shinya, additional, Yoshinari, Satoru, additional, Kidamura, Takashi, additional, Tanabe, Sachiko, additional, Yokota, Satoshi, additional, Kobayashi, Yukiyasu, additional, Nakagawa, Takao, additional, and Nakamura, Takashi, additional

Published
2006
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41. Suzaku and Swift observations for X-ray afterglows; Investigation into the electron acceleration in the internal/external shocks.

Author

Yonetoku, Daisuke, Tanabe, Sachiko, Murakami, Toshio, Emura, N., Aoyama, Y., Kidamura, T., Kodaira, H., Kodama, Y., Kozaka, R., Nashimoto, T., Okuno, S., Yokota, S., Yoshinari, S., Abe, K., Onda, K., Tashiro, M. S., Urata, Y., Nakagawa, Y. E., Sugita, S., and Yamaoka, K.

Subjects
*AFTERGLOW (Physics), *X-ray astronomy, *X-ray spectroscopy, *GAMMA ray bursts, *ARTIFICIAL satellites
Abstract

We have performed ToO observations for three bright GRBs with the Japanese X-ray satellite “Suzaku”. Suzaku strongly supports the follow-up observations by Swift, especially in the late time afterglow phase, with its capabilities of larger effective area and wider energy band compared with Swift/XRT. In this presentation, mainly focusing on the X-ray afterglow of GRB 060904A, we introduce these ToO observation results. In GRB 060904A, we found rapid spectral softening with the photon indices from 1.5 to 5.3 during the steep decay (prompt tail) phase in the BAT and XRT data. This ultra soft spectra suddenly disappeared at the transition time from the prompt tail phase to the shallow decay one. After that, typical afterglow spectra with the photon indices of 2.0 are continuously and preciously monitored by both XRT and Suzaku/XIS up to 1 day since the burst trigger time. To explain this ultra soft spectra, we introduce a spectral cutoff model instead of power-law, and investigate the possibility of the maximum energy of electron distribution. We could successfully trace the temporal history of cutoff energy and it shows the time dependence of ∝t-3∼t-4 while the following afterglow spectra are quite stable. This fact indicates that the emitting material of prompt tail is due to completely different dynamics from the shallow decay component. Therefore we conclude the emission sites of two distinct phenomena obviously differ from each other. [ABSTRACT FROM AUTHOR]

Published
2008
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42. Redshift Dependent Lag-Luminosity Relation in 565 BASTE Gamma Ray Bursts.

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, and Kodama, Yoshiki

Subjects
REDSHIFT, GAMMA ray bursts, GAMMA ray astronomy, GAMMA rays, SPECTRUM analysis
Abstract

We compared redshifts zY measured from Yonetoku relation and zlag from the lag-luminosity relation for 565 BASTE GRBs and were surprised to find that the correlation between these two redshifts is very low. Assuming that the luminosity is a function of both zY and the intrinsic spectral lag τlag, we found a new redshift dependent lag-luminosity relation as L = 7.5×1050 erg/s(1+z)2.53τlag-0.282 with the correlation coefficient of 0.77. [ABSTRACT FROM AUTHOR]

Published
2008
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44. The association between primary open-angle glaucoma and fall: an observational study.

Author

Tanabe, Sachiko, Yuki, Kenya, Ozeki, Naoki, Shiba, Daisuke, and Tsubota, Kazuo

Subjects
*GLAUCOMA, *EYE diseases, *DISEASES in women, *EYE infections, *EYE inflammation
Abstract

Purpose: Falls are among the most serious public health concerns for the elderly. Information conveyed via the visual sense is relevant to postural balance and movement, and proper visual function is essential to avoid falls. Here we investigated the prevalence of injurious falls among patients with primary open-angle glaucoma (POAG) who were more than 45 years old, compared with comparably aged healthy subjects. Methods: This is a cross-sectional study. Consecutive patients who visited the Tanabe Eye Clinic, Yamanashi, Japan between January 1 and March 30, 2009 were screened for eligibility by ophthalmic examination. A total of 117 control subjects (77 men, 40 women; aged 60.2 ± 7.5 years) who were free of ocular disease and 101 POAG patients (58 men, 43 women; aged 62.3 ± 8.7 years) were consecutively enrolled. Participants answered a questionnaire on injurious fall experience during the previous 10 years. The prevalence of injurious fall in subjects with POAG versus healthy controls was examined with Fisher's exact test. Adjusted odds ratios and 95% confidence intervals were estimated with logistic regression models for the subjects with POAG (factors: age, gender, mean deviation in the better eye or worse eye). Results: The self-reported prevalence of injurious fall was 0.9% (1/117) in the control group and 6.9% (7/101) in the POAG group. The association between injurious fall and POAG was statistically significant (P = 0.026, Fisher's exact test). Within the POAG patients, the group reporting falls was significantly older and had a lower BMI, worse BCVA, and worse mean deviation in both the better and worse eye than the group reporting no falls. Worse mean deviation in the eye with the better visual field (odds ratios 0.75; 95% confidence intervals: 0.57 to 0.99; P = 0.036) was a significant risk factor for injurious falls in subjects with POAG. Conclusions: POAG was significantly associated with injurious falls. [ABSTRACT FROM AUTHOR]

Published
2012
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45. Constraints on w0 and w a of dark energy from high-redshift gamma-ray bursts.

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, Kodama, Yoshiki, and Takahashi, Keitaro

Subjects
DARK energy, GAMMA ray bursts, REDSHIFT, GAMMA ray sources, GAMMA rays, GAMMA ray astronomy
Abstract

We extend the Hubble diagram up to using 63 gamma-ray bursts (GRBs) via peak energy–peak luminosity relation (so-called Yonetoku relation), and obtain constraints on cosmological parameters including dynamical dark energy parametrized by . It is found that the current GRB data are consistent with the concordance model within 2σ level. Although constraints from GRBs themselves are not so strong, they can improve the conventional constraints from type Ia supernovae because GRBs have much higher redshifts. Further, we estimate the constraints on the dark energy parameters expected by future observations with Gamma-ray Large Area Space Telescope and Swift by Monte Carlo simulation. Constraints would improve substantially with another 150 GRBs. [ABSTRACT FROM AUTHOR]

Published
2009
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