PG 1407＋265 is a radio quiet quasar that has a relativistic jet.In this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced ...from the jet.We use a simple synchrotron ＋ synchrotron self Compton （SSC） model to fit the emissions with different ratios of energy densities between the magnetic field and electrons （η≡U B/U e）,which predicts a different γ-ray luminosity.The First LAT AGN Catalog （1LAC） did not include PG 1407＋265,which indicates an upper limit of γ-ray luminosity.This upper limit constrains the ratio to be unreasonably large （η≥10^4-5）.This inversely indicates that the optical and X-ray emissions may not be produced from the beaming jet.We discuss the physical implications of these results.
We have monitored the quasar 3C 273 in the optical V, R, and I bands from 2005 to 2016. Intraday variability (IDV) is detected on seven nights. The variability amplitudes on most of the nights are ...less than 10%, and on four nights, more than 20%. When considering the nights with time spans >4 hr, the duty cycle (DC) is 14.17%. Over the 12 years, the overall magnitude and color index variabilities are , , , and , respectively. The largest clear IDV has an amplitude of 42% over just 5.8 minutes, and the weakest detected IDV is 5.4% over 175 minutes. The BWB (bluer when brighter) chromatic trend is dominant for 3C 273 and appears at different flux levels on intraday timescales. The BWB trend exists for short-term timescales and intermediate-term timescales but different timescales have different correlations. There is no BWB trend for our whole time-series data sets. A significant anticorrelation between the BWB trend and length of timescales is found. Combining with V-band data from previous works, we find a possible quasi-periodicity of P = 3918 1112 days. The possible explanations for the observed variability, BWB chromatic trend, and periodicity are discussed.
The relationship between broad line luminosity
L
BLR
and extended radio power
P
E
is investigated. In the log
P
E
-log
L
BLR
diagram, FSRQs populate the region of higher luminosity relative to BL ...Lacs, and FR II BL Lacs are between FSRQs and FR I BL Lacs. For these blazars, there is a significant correlation between
L
BLR
and
P
E
. The regression line scales as
P
E
∝
L
BLR
0.87±0.15
. The slope of this scaling relation is consistent with that derived from the simple theoretical formulae. Thus, the unification of BL Lacs and FRSQs into a single population finds a statistical basis, and a disk-jet symbiosis in blazars is confirmed. FR II BL Lacs are probably at an intermediate stage in the sequence from FSRQs to BL Lacs with FR I BL Lacs at the end of this sequence.
Abstract
We present optical and ultraviolet (UV) observations of a luminous type Ia supernova (SN Ia) SN 2015bq characterized by early flux excess. This SN reaches a
B
-band absolute magnitude at
M
B
...= −19.68 ± 0.41 mag and a peak bolometric luminosity at
L
= (1.75 ± 0.37) × 10
43
erg s
−1
, with a relatively small post-maximum decline rate Δ
m
15
(
B
) = 0.82 ± 0.05 mag. The flux excess observed in the light curves of SN 2015bq a few days after the explosion, especially seen in the UV bands, might be due to the radioactive decay of
56
Ni mixed into the surface. The radiation from the decay of the surface
56
Ni heats the outer layer of this SN. It produces blue
U
−
B
color followed by monotonically reddening in the early phase, dominated iron-group lines, and weak intermediate-mass element absorption features in the early spectra. The scenario of enhanced
56
Ni in the surface is consistent with a large amount of
56
Ni (
M
56
Ni
=
0.97
±
0.20
M
☉
) synthesized during the explosion. The properties of SN 2015bq are found to locate between SN 1991T and SN 1999aa, suggesting the latter two subclasses of SNe Ia may have a common origin.
We continuously monitored the blazar S5 0716+714 in the optical g, r, and i bands from 2017 November 10 to 2019 June 6. The total number of observations is 201 nights including 26,973 data points. ...This is a very large quasi-simultaneous multicolor sample for the blazar. The average time spans and time resolutions are 3.4 hr and 2.9 minutes per night, respectively. During the period of observations, the target source in the r band brightens from 14 16 to 12 29 together with five prominent subflares, and then becomes fainter to 14 76, and again brightens to 12 94 with seven prominent subflares. For the long-term variations, we find a strong flatter-when-brighter (FWB) trend at a low-flux state and then a weak FWB trend at a higher-flux state. A weak FWB trend at a low-flux state and then a strong FWB trend at a higher-flux state are also reported. Most subflares show strong FWB trends, except for two flares with a weak FWB trend. The particle acceleration and cooling mechanisms together with the superposition of the different FWB slopes from the subflares likely explain the optical color behaviors. A scenario of bent jet is discussed.
Background
Bladder cancer (BLCA) is defined as a type of urinary cancer with high incidence and lack of specific biomarkers and drug targets. Immunogenic cell death (ICD) has been classified as a ...regulated type of cell death. Growing evidence suggested that ICD can reshape the tumor immune microenvironment, which may contribute to the development of immunotherapy strategies. The aim of this study was to reveal the specific mechanism of ICD in bladder cancer and to further predict the prognostic immunotherapy outcomes.
Methods
By consensus clustering analysis, bladder cancer patients in TCGA database were divided into different ICD subtypes. Additionally, we developed an ICD-scoring system and constructed the ICD score-based risk signature and nomogram to better characterize patients. Furthermore, we carried out a series of experiments to verify the relevant findings.
Results
Based on the transcriptome expression levels of ICD-related genes, a total of 403 BLCA patients in the TCGA database were divided into two subgroups with different ICD molecular patterns by consensus cluster analysis. These subgroups showed different clinicopathological features, survival outcomes, tumor microenvironment (TME) characteristics, immune-related scores, and treatment response. Moreover, the established prediction model and ICD score can effectively distinguish high risk/score patients from low risk/score patients, which has excellent predictive value. Finally, we found that the key gene HSP90AA1 was highly expressed in the high-ICD score group and in bladder cancer tissues, and was confirmed to be associated with the proliferation of bladder cancer cells.
Conclusion
To sum up, we established a new classification system for BLCA based on ICD-related genes. This stratification has significant predictive power for clinical outcomes and can effectively evaluate the prognosis and immunotherapy of BLCA patients. Finally, it was proved that HSP90AA1 was highly expressed in BLCA and would be a promising therapeutic target for BLCA.
We analyze the radio light curve of 3C 273 at 15 GHz from 1963 to 2006 taken from the database of the literature, and find evidence of quasi-periodic activity. Using the wavelet analysis method to ...analyze these data, our results indicate that: (1) There is one main outburst period of P1=8.1±0.1 year in 3C 273. This period is in a good agreement with Ozernoi’s analysis in optical bands. (2) Based on the possible periods, we expect the next burst in 2014 October.
Based on a large Fermi blazar sample, the blazar sequence (synchrotron peak frequency νpeak versus synchrotron peak luminosity L
peak) is revisited. It is found that there is significant ...anticorrelation between νpeak and L
peak for blazars. However, after Doppler correction the anticorrelation disappears. The jet cavity power (P
jet) is estimated from the extended radio luminosity so that it is free of beaming effects. We find that there are significant anticorrelations between P
jet and the beam-corrected
$\nu _{\rm peak}^{^{\prime }}$
for both blazars and radio galaxies, which supports the blazar sequence and the unification of blazars and radio galaxies (an alternative relationship is the correlation between jet power and γ-ray photon index).
ABSTRACT We have monitored the BL Lac object Mrk 501 in the optical V, R, and I bands from 2010 to 2015. For Mrk 501, the presence of a strong host galaxy component can affect the results of ...photometry. After subtracting the host galaxy contributions, the source shows intraday and long-term variabilities for optical flux and color indices. The average variability amplitudes of the V, R, and I bands are , respectively, and the value of the duty cycle is 14.87%. A minimal variability timescale of 106 minutes is detected. No significant time lag between the V and I bands is found on one night. The bluer-when-brighter (BWB) trend is dominant for Mrk 501 on intermediate, short, and intraday timescales, which supports the shock-in-jet model. For the long timescale, Mrk 501, in different states, can have different BWB trends. The corresponding results for non-correcting host galaxy contributions are also presented.
PDF
