Tracking the Complex Absorption in NGC 2110 with Two Suzaku Observations

We present spectral analysis of two Suzaku observations of the Seyfert 2 galaxy, NGC 2110. This source has been known to show complex, variable absorption which we study in depth by analyzing these two observations set seven years apart and by comparing to previously analyzed observations with the XMM-Newton and Chandra observatories. We find that there is a relatively stable, full-covering absorber with a column density of ~3$\times 10 ^{22}$ cm$^{-2}$, with an additional patchy absorber that is likely variable in both column density and covering fraction over timescales of years, consistent with clouds in a patchy torus or in the broad line region. We model a soft emission line complex, likely arising from ionized plasma and consistent with previous studies. We find no evidence for reflection from an accretion disk in this source with no contribution from relativistically broadened Fe Ka line emission nor from a Compton reflection hump.Comment: Accepted to ApJ: March, 201

Intra-leaf gradients of photoinhibition induced by different color lights: Implications for the dual mechanisms of photoinhibition and for the application of conventional chlorophyll fluorometers

We studied how different color lights cause gradients of photoinhibition within a leaf, to attempt to resolve the controversy whether photon absorption by chlorophyll or Mn is the primary cause of photoinhibition, suggested by the excess-energy hypothesis or the two-step hypothesis, respectively. Lincomycin-treated leaf-discs were photoinhibited by white, blue, green or red light. Combining a micro-fiber fluorometer, a fiber-thinning technique and a micro-manipulator enabled us to measure the chlorophyll fluorescence signals within a leaf. Photoinhibition gradients were also compared with results from various conventional fluorometers to estimate their depth of signal detection. The severity of photoinhibition was in the descending order of blue, red and green light near the adaxial surface, and in the descending order of blue, green and red light in deeper tissue, which is correlated with the chlorophyll and Mn absorption spectrum, respectively. These results cannot be explained by either hypothesis alone. These data strongly suggest that (1) both the excess-energy and the two-step mechanisms occur in photoinhibition, and (2) fluorometers with red or blue measuring light give overestimated or underestimated Fv/Fm values of photoinhibited leaves compared with the whole tissue average, respectively; that is, they measured deeper or shallower leaf tissue, respectively

Precision Fe Kalpha and Fe Kbeta Line Spectroscopy of the Seyfert 1.9 Galaxy NGC 2992 with Suzaku

We present detailed time-averaged X-ray spectroscopy in the 0.5--10 keV band of the Seyfert~1.9 galaxy NGC 2992 with the Suzaku X-ray Imaging Spectrometers (XIS). We model the complex continuum in detail. There is an Fe K line emission complex that we model with broad and narrow lines and we show that the intensities of the two components are decoupled at a confidence level >3sigma. The broad Fe K line has an EW of 118 (+32,-61) eV and could originate in an accretion disk (with inclination angle greater than ~30 degrees). The narrow Fe Kalpha line has an EW of 163 (+47,-26) eV and is unresolved FWHM <4090 km/s) and likely originates in distant matter. The absolute flux in the narrow line implies that the column density out of the line-of-sight could be much higher than measured in the line-of-sight, and that the mean (historically-averaged) continuum luminosity responsible for forming the line could be a factor of several higher than that measured from the data. We also detect the narrow Fe Kbeta line with a high signal-to-noise ratio and describe a new robust method to constrain the ionization state of Fe responsible for the Fe Kalpha and Fe Kbeta lines that does not require any knowledge of possible gravitational and Doppler energy shifts affecting the line energies. For the distant line-emitting matter (e.g. the putative obscuring torus) we deduce that the predominant ionization state is lower than Fe VIII (at 99% confidence), conservatively taking into account residual calibration uncertainties in the XIS energy scale and theoretical and experimental uncertainties in the Fe K fluorescent line energies. From the limits on a possible Compton-reflection continuum it is likely that the narrow Fe Kalpha and Fe Kbeta lines originate in a Compton-thin structure.Comment: Abstract is abridged. Accepted for publication in the Suzaku special issue of PASJ (November 2006). 18 pages, 6 figure

A Stringent Limit on the Accretion Luminosity of the Possible Central Black Hole in the Globular Cluster M15

The globular cluster M15 has recently been found to host a possible central black hole with a mass of ~2000 solar masses. A deep, high-resolution Chandra image failed to detect the "nucleus" of the cluster in X-rays. The upper limit on the X-ray luminosity (L_x < 5.6x10^32 erg/s) corresponds to a bolometric Eddington ratio of L_bol/L_Edd < (2-4)x10^-8. Combining this limit with an estimate of the electron density of the intracluster ionized plasma derived from pulsar dispersion measures, we show that the radiative efficiency of the accretion flow, if it accretes at the Bondi rate, must be much lower than that of a standard optically thick, geometrically thin disk.Comment: To appear in ApJ (Letters). 4 page

Wide-band spectroscopy of the Compton thick Seyfert 2 galaxy Mrk 3 with Suzaku

We obtained a wide-band spectrum of the Compton-thick Seyfert 2 galaxy Mrk 3 with Suzaku. The observed spectrum was clearly resolved into weak, soft power-law emission, a heavily absorbed power-law component, cold reflection, and many emission lines. The heavily absorbed component, absorbed by gas with a column density of 1.1x10^24 cm^-2, has an intrinsic 2--10 keV luminosity of ~1.6x10^43 erg s^-1, and is considered to be direct emission from the Mrk 3 nucleus. The reflection component was interpreted as reflection of the direct light off cold, thick material; the reflection fraction $R$ was 1.36+/-0.20. The cold material is inferred to be located > 1 pc from the central black hole of Mrk 3 due to the low ionization parameter of iron (xi < 1 erg cm s^-1) and the narrow iron line width (s < 22 eV). A Compton shoulder to the iron line was detected, but the intensity of the shoulder component was less than that expected from spherically distributed Compton-thick material. The weak, soft power-law emission is considered to be scattered light by ionized gas. The existence of many highly-ionized lines from O, Ne, Mg, Si, S, and Fe in the observed spectrum indicates that the ionized gas has a broad ionized structure, with xi=10--1000. The scattering fraction with respect to the direct light was estimated to be 0.9+/-0.2%, which indicates that the column density of the scattering region is about 3.6x10^22 cm^-2. This high-quality spectrum obtained by Suzaku can be considered a template for studies of Seyfert 2 galaxies.Comment: 24 pages, 8 figures, accepted in PASJ for publicatio

Long-Term Outcome of Proton Therapy and Carbon-Ion Therapy for Large (T2a–T2bN0M0) Non–Small-Cell Lung Cancer

IntroductionAlthough many reports have shown the safety and efficacy of stereotactic body radiotherapy (SBRT) for T1N0M0 non–small-cell lung cancer (NSCLC), it is rather difficult to treat T2N0M0 NSCLC, especially T2b (>5 cm) tumor, with SBRT. Our hypothesis was that particle therapy might be superior to SBRT in T2 patients. We evaluated the clinical outcome of particle therapy for T2a/bN0M0 NSCLC staged according to the 7th edition of the International Union Against Cancer (UICC) tumor, node, metastasis classification.MethodsFrom April 2003 to December 2009, 70 histologically confirmed patients were treated with proton (n = 43) or carbon-ion (n = 27) therapy according to institutional protocols. Forty-seven patients had a T2a tumor and 23 had a T2b tumor. The total dose and fraction (fr) number were 60 (Gray equivalent) GyE/10 fr in 20 patients, 52.8 GyE/4 fr in 16, 66 GyE/10 fr in 16, 80 GyE/20 fr in 14, and other in four patients, respectively. Toxicities were scored according to the Common Terminology Criteria for Adverse Events, Version 4.0.ResultsThe median follow-up period for living patients was 51 months (range, 24–103). For all 70 patients, the 4-year overall survival, local control, and progression-free survival rates were 58% (T2a, 53%; T2b, 67%), 75% (T2a, 70%; T2b, 84%), and 46% (T2a, 43%; T2b, 52%), respectively, with no significant differences between the two groups. The 4-year regional recurrence rate was 17%. Grade 3 pulmonary toxicity was observed in only two patients.ConclusionParticle therapy is well tolerated and effective for T2a/bN0M0 NSCLC. To further improve treatment outcome, adjuvant chemotherapy seems a reasonable option, whenever possible

ALMA Observations of the Submillimeter Dense Molecular Gas Tracers in the Luminous Type-1 Active Nucleus of NGC 7469

We present ALMA Cycle 1 observations of the central kpc region of the luminous type-1 Seyfert galaxy NGC 7469 with unprecedented high resolution (0.5$"$ $\times$ 0.4$"$ = 165 pc $\times$ 132 pc) at submillimeter wavelengths. Utilizing the wide-bandwidth of ALMA, we simultaneously obtained HCN(4-3), HCO$^+$(4-3), CS(7-6), and partially CO(3-2) line maps, as well as the 860 $\mu$m continuum. The region consists of the central $\sim$ 1$"$ component and the surrounding starburst ring with a radius of $\sim$ 1.5$"$-2.5$"$. Several structures connect these components. Except for CO(3-2), these dense gas tracers are significantly concentrated towards the central $\sim$ 1$"$, suggesting their suitability to probe the nuclear regions of galaxies. Their spatial distribution resembles well those of centimeter and mid-infrared continuum emissions, but it is anti-correlated with the optical one, indicating the existence of dust obscured star formation. The integrated intensity ratios of HCN(4-3)/HCO$^+$(4-3) and HCN(4-3)/CS(7-6) are higher at the AGN position than at the starburst ring, which is consistent to our previous findings (submm-HCN enhancement). However, the HCN(4-3)/HCO$^+$(4-3) ratio at the AGN position of NGC 7469 (1.11$\pm$0.06) is almost half of the corresponding value of the low-luminosity type-1 Seyfert galaxy NGC 1097 (2.0$\pm$0.2), despite the more than two orders of magnitude higher X-ray luminosity of NGC 7469. But the ratio is comparable to that of the close vicinity of the AGN of NGC 1068 ($\sim$ 1.5). Based on these results, we speculate that some other heating mechanisms than X-ray (e.g., mechanical heating due to AGN jet) can contribute significantly for shaping the chemical composition in NGC 1097.Comment: Fixed typos in the title. 15 pages, 8 figures, 4 tables: accepted for publication in ApJ. Comments welcom

Feasibility and efficacy of hepatic arterial infusion chemotherapy for advanced hepatocellular carcinoma after sorafenib

Aim: Sorafenib is the standard treatment for advanced hepatocellular carcinoma (HCC). However, although there is no proven therapeutic procedure following the termination of sorafenib, hepatic arterial infusion chemotherapy (HAIC) may be a treatment option in advanced HCC. The aim of this study was to evaluate feasibility and efficacy of HAIC for patients with advanced HCC as subsequent therapy. Methods: We retrospectively evaluated 27 consecutive patients with advanced HCC who were treated with HAIC following sorafenib between June 2009 and December 2012 at our hospital. Cisplatin (20 mg/m2 per day) was administered via the hepatic artery for 10 min, prior to the continuous administration of 5-fluorouracil (330 mg/m2 per day) over 24 h from days 1-5 and 8-12 and the s.c. administration of pegylated interferon α-2b (1 μg/kg) on days 1, 8, 15, and 22. A treatment cycle consisted of 28 days of drug administration followed by 14 days of rest. Results: The toxicity profile showed that hematological toxicities were common, and grade 3/4 neutropenia and thrombocytopenia were observed (51.9% and 48.1%, respectively). Five patients (18.5%) experienced device-related complications. No unexpected adverse reactions and no treatmentrelated deaths were observed. Partial response was obtained in eight patients (29.6%), and stable disease was noted in nine patients (33.3%). Median progression-free survival and median survival time from initiation of HAIC were 4.0 and 7.6 months, respectively. Conclusions: Because HAIC was well tolerated and exhibited moderate antitumor activity, it is a potentially useful treatment procedure in patients with advanced HCC even after failure of sorafenib

Proton beam therapy for intrahepatic cholangiocarcinoma: A multicenter prospective registry study in Japan

Introduction: Intrahepatic cholangiocarcinoma (ICC) can be treated with chemotherapy in unresectable cases, but outcomes are poor. Proton beam therapy (PBT) may provide an alternative treatment and has good dose concentration that may improve local control. Methods: Fifty-nine patients who received initial PBT for ICC from May 2016 to June 2018 at nine centers were included in the study. The treatment protocol was based on the policy of the Japanese Society for Radiation Oncology. Forty patients received 72.6-76 Gy (RBE) in 20-22 fr, 13 received 74.0-76.0 Gy (RBE) in 37-38 fr, and 6 received 60-70.2 Gy (RBE) in 20-30 fr. Overall survival (OS) and progression-free survival (PFS) were estimated by Kaplan-Meier analysis. Results: The 59 patients (35 men, 24 women; median age 71 years; range 41-91 years) had PS of 0 (n=47), 1 (n=10) and 2 (n=2). Nine patients had hepatitis and all 59 cases were considered inoperable. The Child-Pugh class was A (n=46), B (n=7), and unknown (n=6); the median maximum tumor diameter was 5.0 cm (range 2.0-15.2 cm); and the clinical stage was I (n=12), II (n=19), III (n=10), and IV (n=18). At the last follow-up, 17 patients were alive (median follow-up 36.7 months; range 24.1-49.9 months) and 42 had died. The median OS was 21.7 months (95% CI 14.8-34.4 months). At the last follow-up, 37 cases had recurrence, including 10 with local recurrence. The median PFS was 7.5 months (95% CI 6.1-11.3 months). In multivariable analyses, Child-Pugh class was significantly associated with OS and PFS, and Child-Pugh class and hepatitis were significantly associated with local recurrence. Four patients (6.8%) had late adverse events of Grade 3 or higher. Discussion/Conclusion. PBT gives favorable treatment outcomes for unresectable ICC without distant metastasis and may be particularly effective in cases with large tumors