For longevity in the market, manufacturers must strike a balance between monetary benefits and production capability. This article investigates distributed hybrid flowshop scheduling problem with deteriorating jobs, objective of minimizing makespan mean tardiness. A mathematical model for is constructed. To minimize goals, multi-objective discrete differential evolution (MODDE) method put forward. achieving optimization two-strategy initialization operation forth. local search strategy...

Abstract By means of astronomical observation data from the 60 cm Telescope at Yunnan Observatory, optical in g, r , and i bands were collected for BL Lac S5 0716+714, spanning 2017 November 10 to 2018 May 15. The original set contains 21,396 quasi-simultaneous multiband points, with 7132 points each band. Lomb–Scargle periodogram method weighted wavelet Z-transform used search a quasi-periodic oscillation (QPO) signal data. For first time, we report QPO 44 ± 6 days final significance 3.98 σ...

Abstract 1LHAASO J0249+6022 is an extended very-high-energy γ -ray source discovered by the Large High-Altitude Air Shower Observatory. Based on nearly 16.1 yr of data from Fermi Area Telescope, we report probable emission in 0.03–1 TeV energy range. The results show that its spectrum can be well fitted a single power law with index 1.54 ± 0.17, and integral photon flux (4.28 1.03) × 10 −11 photons cm −2 s −1 . We also considered theoretically whether nonthermal could originate pulsar wind...

Abstract The pulsar wind nebula CTB 87 (G74.9+1.2) is one of the sources emitting γ -rays with energies higher than 10 TeV, as measured by Very Energetic Radiation Imaging Telescope Array System telescope. In this study, we undertake a reanalysis GeV emission from region, utilizing ∼16 yr high-energy -ray data collected Fermi Large Area Telescope. energy range 0.03–1 spectrum can be adequately described power-law model an index 1.34 ± 0.18, and integral flux calculated to (7.25 1.36) × −13...

ABSTRACT We report a detection of GeV γ-ray emission potentially originating from the pulsar wind nebula in CTA 1 by analysing about 15 yr Fermi Large Area Telescope data. By selecting an energy range 50 to TeV remove contamination PSR J0007+7303, we have discovered extended source with test statistic value ∼44.94 region 1. The obtained flux is measured be 6.71 ± 2.60 × 10−12 erg cm−2 s−1 spectral index 1.61 0.36, which allows for smooth connection band. also considered associated 1LHAASO...

We carried out a high time-resolution, multicolour optical observing campaign for eight $\gamma$-ray detected blazars during 2010-2020. analyze flux variations, correlations between magnitudes and colours on different timescales. Intraday variability (IDV) is in all sources of our sample. A bluer-when-brighter (BWB) chromatic trend dominant intraday On the short timescales, BWB only shows up ON 231, 3C 279, BL Lacertae 1E 1458.8+2249. There 279 long timescale. estimate upper limits black...

Abstract We analyze the quasiperiodic oscillation (QPO) of historical light curve flat-spectrum radio quasars PKS 0405-385 detected by Fermi Large Area Telescope from 2008 August to 2021 November. To identify and determine QPO signal in γ -ray curve, we use four time series analysis techniques based on frequency domains, i.e., Lomb–Scargle periodogram (LSP), weighted wavelet z -transform (WWZ), REDFIT, epoch folding. The results show that has a behavior ∼2.8 yr with significance ∼4.3 σ...

We systematically search for quasiperiodic oscillatory (QPO) signals on the month timescale among 1525 sources given in Fermi Large Area Telescope Light Curve Repository. find a transient QPO of 31.3$\pm$1.8 days gamma-ray band light curve TeV blazar S5 0716+714, which has seven cycles (MJD 55918-56137) first time by weighted wavelet Z-transform and Lomb-Scargle periodogram methods. Monte Carlo simulations based power spectral density probability distribution function were used to evaluate...

Abstract In this work, we report periodicity search analyses in the gamma-ray light curve of blazar S4 0954+658 monitoring undertaken by Fermi Large Area Telescope. Four analytical methods and a tool are adopted to detect any periodic flux modulation corresponding significance level, revealing: (i) quasi-periodic oscillation (QPO) 66 days with level >5 σ spanning over 600 from 2015 2016 (MJD 57,145–57,745), resulting continuous observation nine cycles, which is one longest cycles...

LHAASO J1908+0621 has been recently detected as a source emitting $\gamma$-rays with energies above 100 TeV, and the multiband observations show that break around 1 TeV appears in $\gamma$-ray spectrum. We have reanalyzed GeV properties for using 14 years of data recorded by Fermi Large Area Telescope (Fermi-LAT). The spectrum energy range 30-500 an index 1.50 $\pm$ 0.26, which is much smaller than $\gamma$-rays. Additionally, radiation this are investigated based on one-zone time-dependent...

Abstract The variability data for the BL Lacertae object TXS 1902+556 in optical and γ-ray wavebands were obtained from 0.76 m Katzman Automatic Imaging Telescope Fermi Large Area (Fermi-LAT), covering periods of 14.4 years 14.7 years, respectively. properties systematically analyzed, with particular emphasis on first comprehensive investigation radiation variation waveband. Four well-established techniques employed this purpose: Lomb-Scargle periodogram, REDFIT program, Jurkevich method,...

Abstract We propose a jet helical motion model to explain the γ -ray quasiperiodic oscillation of PG 1553+113. In this model, we hypothesize that relativistic with constant angular velocity rotates around axis, causing Doppler factor vary over time, leading periodic changes in flux. addition, consider parameters emission field slightly during observation period and can be obtained by directly fitting their multiwavelength spectra. Then, use resulting information reproduce light curve. Our...

ABSTRACT N 157B located in the Large Magellanic Cloud is first pulsar wind nebula detected outside of Galaxy γ-rays. In this paper, we analyse emission above 30 GeV from using ∼14.3 yr Fermi-LAT data. The γ-ray spectrum between and 500 well described by a single power-law function with photon index 1.83 ± 0.26, its integral flux (4.10 0.83) × 10−11 photons cm−2 s−1. We adopt one-zone leptonic model to investigate whether multiband non-thermal target source can be generated synchrotron...

Abstract We have systemically studied the properties of 1ES 1959+650, specifically its multiband variability and emission mechanisms. carefully analyze by four different kinds trusted approaches. In contrast with previous research thanks to our more detailed data, we find that an unprecedented significant quasi-periodic component timescale <?CDATA $P={266.2}_{-7.2}^{+7.5}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>P</mml:mi> <mml:mo>=</mml:mo>...

We report a detection of GeV $\gamma$-ray emission potentially originating from the pulsar wind nebula in CTA 1 by analyzing about 15 yr Fermi Large Area Telescope data. By selecting an energy range 50 to TeV remove contamination PSR J0007+7303, we have discovered extended source with TS value $\sim$ 44.94 region 1. The obtained flux is measured be 6.71 $\pm$ 2.60 $\times$ $10^{-12}$ erg $\mathrm{cm}^{-2}$ $\mathrm{s}^{-1}$ spectral index 1.61 0.36, which allows for smooth connection band....

ABSTRACT The observation data of blazar 1ES 1426+42.8 were obtained using the 1.02 m optical telescope Yunnan Observatories during 2021 to 2023. Intraday variability (IDV) is detected on seven nights. We use turbulent model investigate mechanism IDV in 1426+42.8. fitting light curves match actual well. Using this model, we obtain parameters such as size cells and width pulses jet. A possible short-lived quasi-periodic oscillation (QPO) $58.55 \pm 8.09$ min was 2022 April 26 whose curve...

Abstract We present periodicity search analyses on the long-term γ -ray light curve of BL Lacertae object 4FGL J2139.4−4235 observed by Fermi Large Area Telescope, over a period more than 15 yr, from 2008 August 4 to 2023 December 10. To determine quasiperiodic oscillation (QPO) behavior in 0.3–300 GeV energy range, we used four methods, namely Lomb–Scargle periodogram, weighted wavelet z-transform, phase dispersion minimization, and autoregressive integrated moving average model. A Monte...

Abstract HESS J1420−607 is a γ -ray emitting source associated with the pulsar wind nebula (PWN) powered by energetic PSR J1420−6048. Based on 14 yr of data obtained Fermi Large Area Telescope, we re-analyzed its GeV radiative properties, resulting in detailed spectra within band 10–200 GeV. Moreover, use one-zone time-dependent model for multiband nonthermal emission from nebulae to investigate properties J1420−607. Assuming that electrons/positrons are injected into PWN broken power law...

Abstract HESS J1303-631 is an extended TeV pulsar wind nebula powered by the PSR J1301-6305 detected with High Energy Stereoscopic System. We present analysis of GeV γ -ray region about 14 yr Fermi Large Area Telescope data. The emission, coincident very-high-energy source, has a photon index 1.69 ± 0.09 in 10–500 band, and morphology extension to same direction as indicated band. Moreover, observed multi-wavelength spectral energy distribution studied one-zone time-dependent leptonic model,...

In this work, we report periodicity search analyses in the gamma-ray light curve of blazar S4 0954+658 monitoring undertaken by Fermi Large Area Telescope (LAT). Four analytical methods and a tool are adopted to detect any periodic flux modulation corresponding significance level, revealing that (i) 66 d quasi-periodic oscillation (QPO) with level $&gt; 5σ$ spanning over 600 from 2015 2016 (MJD 57145--57745), resulting continuous observation nine cycles, which is one highest cycles discerned...

LHAASO J1908+0621 has been recently detected as a source emitting $γ$-rays with energies above 100 TeV, and the multiband observations show that break around 1 TeV appears in $γ$-ray spectrum. We have reanalyzed GeV properties for using 14 years of data recorded by Fermi Large Area Telescope (Fermi-LAT). The spectrum energy range 30-500 an index 1.50 $\pm$ 0.26, which is much smaller than $γ$-rays. Additionally, radiation this are investigated based on one-zone time-dependent model. In...

Abstract In this work, we have assembled the long‐term variability data of blazar 4FGL J0650.7 + 2503 in γ‐ray and optical bands, spanning about 11.9 8.6 years, respectively. The light curves are then analyzed by using Lomb‐Scargle Periodogram, Weighted Wavelet Z‐transform, Jurkevich discrete correlation function techniques, results reveal two possible timescales quasi‐periodic oscillation: 500 ± 37 days for 330 20 optical. To explore origin γ‐ray, investigated between band correlations,...