X-ray Band Research Articles

X-ray Observations of the Intermediate Polar TX Col

We present the timing analysis of the intermediate polar TX Col in the X-ray band using the observations made by Chandra, Swift, and Suzaku during the years 2000, 2007, and 2009, respectively. The spin, orbital, and beat periods derived from these data are consistent with the earlier findings. We found that the spin modulation was dominant during the Chandra observation, whereas both orbital and beat modulations were dominant during the Swift and Suzaku observations. These findings and past X-ray observations indicate that TX Col is changing its accretion geometry from disc dominance to stream dominance and vice versa.

Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. I. Discovery of Prominence Eruptions Associated with Superflares

Young solar-type stars frequently produce superflares, serving as a unique window into the young Sun-Earth environments. Large solar flares are closely linked to coronal mass ejections (CMEs) associated with filament/prominence eruptions, but observational evidence for stellar superflares remains scarce. Here, we present a 12-day, multiwavelength campaign observation of young solar-type star EK Draconis (G1.5V, 50–120 Myr age) utilizing the Transiting Exoplanet Survey Satellite, the Neutron star Interior Composition ExploreR, and the Seimei telescope. The star has previously exhibited blueshifted Hα absorptions as evidence for a filament eruption associated with a superflare. Our simultaneous optical and X-ray observations identified three superflares of 1.5 × 1033–1.2 × 1034 erg. We report the first discovery of two prominence eruptions on a solar-type star, observed as blueshifted Hα emissions at speeds of 690 and 430 km s−1 and masses of 1.1 × 1019 and 3.2 × 1017 g, respectively. The faster, massive event shows a candidate of post-flare X-ray dimming with the amplitude of up to ∼10%. Several observational aspects consistently point to the occurrence of a fast CME associated with this event. The comparative analysis of the estimated length scales of flare loops, prominences, possible dimming region, and starspots provides the overall picture of the eruptive phenomena. Furthermore, the energy partition of the observed superflares in the optical and X-ray bands is consistent with flares from the Sun, M-dwarfs, and close binaries, yielding the unified empirical relations. These discoveries provide profound implications of the impact of these eruptive events on early Venus, Earth, and Mars and young exoplanets.

On joint analysing <i>XMM-NuSTAR</i> spectra of active galactic nuclei

A recently released <i>XMM-Newton</i> note revealed a significant calibration issue between nuclear spectroscopic telescope array (<i>NuSTAR)</i> and <i>XMM-Newton</i> European Photon Imaging Camera (EPIC) and provided an empirical correction to the EPIC effective area. To quantify the bias caused by the calibration issue in the joint analysis of <i>XMM-NuSTAR</i> spectra and verify the effectiveness of the correction, in this work, we perform joint-fitting of the <i>NuSTAR</i> and EPIC-pn spectra for a large sample of 104 observation pairs of 44 X-ray bright active galactic nuclei (AGN). The spectra were extracted after requiring perfect simultaneity between the <i>XMM-Newton</i> and <i>NuSTAR</i> exposures (merging Good Time Intervals, GTIs from two missions) to avoid bias due to the rapid spectral variability of the AGN. Before the correction, the EPIC-pn spectra are systematically harder than the corresponding <i>NuSTAR</i> spectra by <inline-formula><tex-math id="M1">\begin{document}$\Delta \varGamma \sim 0.1 $\end{document}</tex-math><alternatives><graphic specific-use="online" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="JUSTC-2023-0160_M1.jpg"/><graphic specific-use="print" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="JUSTC-2023-0160_M1.png"/></alternatives></inline-formula>, subsequently yielding significantly underestimated cutoff energy <i>E</i><sub>cut</sub> and the strength of reflection component <i>R</i> when performing joint-fitting. We confirm that the correction is highly effective and can commendably erase the discrepancy in best-fit <i>Γ</i>, <i>E</i><sub>cut</sub>, and <i>R</i>. We thus urge the community to apply the correction when joint-fitting <i>XMM</i>-<i>NuSTAR</i> spectra, but note that the correction is limited to 3–12 keV and therefore not applicable when the soft X-ray band data are included. Besides, we show that as merging GTIs from two missions would cause severe loss of <i>NuSTAR</i> net exposure time, in many cases, joint-fitting yields no advantage compared with utilizing <i>NuSTAR</i> data alone. We finally present a technical note on filtering periods of high background flares for <i>XMM-Newton</i> EPIC-pn exposures in the Small Window mode.

A Statistical Study of Soft X-Ray Flares on Solar-type Stars

The statistical characteristics of stellar flares at optical bands have received extensive study, but they remain to be studied at soft X-ray bands, in particular for solar-type stars. Here, we present a statistical study of soft X-ray flares on solar-type stars, which can help in understanding the multiwavelength behaviors of stellar flares. We mainly use Chandra Source Catalog Release 2.0, which includes a number of flaring stars with denoted variability, and Gaia Data Release 3, which includes the necessary information for classifying stars. We also develop a set of methods for identifying and classifying stellar soft X-ray flares and estimating their properties. A detailed statistical investigation of 129 flare samples on 103 nearby solar-type stars as selected yields the following main results. (1) The flare energy emitted at the soft X-ray band in our sample ranges from ∼1033 to ∼1037 erg, and the majority of them are superflares, with the most energetic one having energy of 6.0−4.7+3.2×1037erg . (2) The flare duration is related to its energy as formulated by Tduration,SXR∝Eflare,SXR0.201±0.024 , which is different from those derived at optical and near-IR bands, indicating distinct radiation mechanisms at different bands. (3) The frequency distribution of stellar flares as a function of energy is formulated as dNflare/dEflare,SXR∝Eflare,SXR−1.77 , which is similar to the results found at other bands and on other types of stars, indicating that the energy emitted at the soft X-ray band could be a constant fraction of the full-band bolometric energy.

Distinguishing the impact and signature of black holes from different origins in early cosmic history

ABSTRACT We semi-analytically model the effects of primordial black hole (PBH) accretion on the cosmic radiation background during the epoch of reionization (z ≳ 6). PBHs in the intergalactic medium (IGM) and haloes, where star formation can occur, are considered. For stars with a mass $\gtrsim 25 \rm \ {\rm M}_{\odot }$, formed in suitable host haloes, we assume they quickly burn out and form stellar-remnant black holes (SRBHs). These SRBHs, like PBHs, also accrete material, and are considered to have similar radiation feedback in the halo environment. To improve the background radiation estimation, we consider the impact of PBHs on structure formation, allowing a modified halo mass function. We consider the radiation feedback from a broad suite of black holes: PBHs, SRBHs, high-mass X-ray binaries, and supermassive black holes. The result shows that at z ≳ 30, the radiation background energy density is generated by PBHs accreting in the IGM, whereas at lower redshifts, halo accretion dominates. We also dissect the total power density by modelling the accretion spectral energy distribution across different wavebands. In the UV band, we find that for fPBH ≲ 10−3, the H-ionizing and Lyman-α fluxes from PBH accretion feedback do not violate existing constraints on the timing of reionization, and on the effective Wouthuysen–Field coupling of the 21-cm spin temperature of neutral hydrogen to the IGM kinetic temperature. However, in the X-ray band, with the same abundance, PBHs contribute significantly and could explain the unresolved part of the cosmic X-ray background.

A Multiwavelength Investigation of PSR J2229+6114 and its Pulsar Wind Nebula in the Radio, X-Ray, and Gamma-Ray Bands

G106.3+2.7, commonly considered to be a composite supernova remnant (SNR), is characterized by a boomerang-shaped pulsar wind nebula (PWN) and two distinct (“head” and “tail”) regions in the radio band. A discovery of very-high-energy gamma-ray emission (E γ > 100 GeV) followed by the recent detection of ultrahigh-energy gamma-ray emission (E γ > 100 TeV) from the tail region suggests that G106.3+2.7 is a PeVatron candidate. We present a comprehensive multiwavelength study of the Boomerang PWN (100″ around PSR J2229+6114) using archival radio and Chandra data obtained two decades ago, a new NuSTAR X-ray observation from 2020, and upper limits on gamma-ray fluxes obtained by Fermi-LAT and VERITAS observatories. The NuSTAR observation allowed us to detect a 51.67 ms spin period from the pulsar PSR J2229+6114 and the PWN emission characterized by a power-law model with Γ = 1.52 ± 0.06 up to 20 keV. Contrary to the previous radio study by Kothes et al., we prefer a much lower PWN B-field (B ∼ 3 μG) and larger distance (d ∼ 8 kpc) based on (1) the nonvarying X-ray flux over the last two decades, (2) the energy-dependent X-ray size of the PWN resulting from synchrotron burn-off, and (3) the multiwavelength spectral energy distribution (SED) data. Our SED model suggests that the PWN is currently re-expanding after being compressed by the SNR reverse shock ∼1000 yr ago. In this case, the head region should be formed by GeV–TeV electrons injected earlier by the pulsar propagating into the low-density environment.

Soft X-ray and FUV observations of Nova Her 2021 (V1674 Her) with AstroSat

ABSTRACT Nova Her 2021 or V1674 Her was one of the fastest novae to be observed so far. We report here the results from our timing and spectral studies of the source observed at multiple epochs with AstroSat. We report the detection of a periodicity in the source in soft X-rays at a period of 501.4–501.5 s which was detected with high significance after the peak of the super-soft phase, but was not detected in the far ultraviolet (FUV) band of AstroSat. The shape of the phase-folded X-ray light curves has varied significantly as the nova evolved. The phase-resolved spectral studies reveal the likely presence of various absorption features in the soft X-ray band of 0.5–2 keV, and suggest that the optical depth of these absorption features may be marginally dependent on the pulse phase. Strong emission lines from Si, N, and O are detected in the FUV, and their strength declined continuously as the nova evolved and went through a bright X-ray state.

The Influence of Increased Electron Energy Spread on the Radiation of the Second Harmonic in Free Electron Lasers

Free electron lasers (FELs) are becoming more and more popular as sources of radiation for research purposes in many fields of science. They are frequently employed in second harmonic generation (SHG) studies. SHG is an important effect of nonlinear responses of matter to irradiation. It should be separated from the second harmonic of the radiation source, FELs, for correct analysis of the response. Using an analytical model for harmonic powers evolution in a single-pass FEL, we demonstrate the dependence of FEL harmonics on the key parameters of beams and undulators and show that it is possible to reduce the second FEL harmonic content if the energy spread of an electron beam is increased. For LEUTL FEL radiation in the visible range, we analytically demonstrate a reduction in the second harmonic power by an order of magnitude if electron energy spread is increased twice, which still allows efficient bunching at the fundamental wavelength. The method is valid regardless of the photon energy and, therefore, the absorption edge of the target material, and as such, it is valid also in the X-ray band.

Can FSRQ 3C 345 be a very high energy blazar candidate?

ABSTRACT The recent detection of very high energy (VHE) emissions from flat spectrum radio quasars (FSRQs) at high redshifts has revealed that the universe is more transparent to VHE γ-rays than it was expected. It has also questioned the plausible VHE emission mechanism responsible for these objects. Particularly for FSRQs, the γ-ray emission is attributed to the external Compton (EC) process. We perform a detailed spectral study of Fermi-detected FSRQ 3C 345 using synchrotron, synchrotron self-Compton, and EC emission mechanisms. The simultaneous data available in optical, ultraviolet, X-ray, and γ-ray energy bands is statistically fitted under these emission mechanisms using the χ2-minimization technique. Three high flux states and one low flux state are chosen for spectral fitting. The broad-band spectral energy distribution during these flux states is fitted under different target photon temperatures, and the model VHE flux is compared with the 50 h Cherenkov Telescope Array sensitivity. Our results indicate a significant VHE emission could be attained during the high flux state from MJD 59635−59715 when the target photon temperature is within 900–1200 K. Furthermore, our study shows a clear trend of variation in the bulk Lorentz factor of the emission region as the source transits through different flux states. We also note that during high γ-ray flux states, an increase in external photon temperature demands high bulk Lorentz factors, while this behaviour reverses in case of low γ-ray flux state.

A fresh perspective on the 3D dynamics of Tycho’s supernova remnant: Ejecta asymmetries in the X-ray band

Context. Even 450 yr after the explosion of the Type Ia SN 1572, the dynamics of the Tycho supernova remnant (Tycho’s SNR) can offer keys to improving our understanding of the explosion mechanism and the interaction of the remnant with the interstellar medium. Aims. To probe the asymmetries and the evolution of the SNR, we tracked the ejecta dynamics using new methods applied to the deep X-ray observations available in the Chandra space telescope archive. Methods. For the line-of-sight (LoS) velocity measurement (Vz), we used the Doppler effect focused on the bright Si line in the 1.6-2.1 keV band. Using the component separation tool called general morphological component analysis (GMCA), we successfully disentangled the red and blueshifted Si ejecta emission. This allowed us to reconstruct a map of the peak energy of the silicon line with a total coverage of the SNR at a 2″ resolution. We then obtained a proxy of the integrated velocity along the LoS. For the proper motions in the plane of the sky (Vxy), we developed a new method, called Poisson optical flow (POF), to measure the displacement of two-dimensional (2D) features between the observations of 2003 and 2009. The result is a field of around 1700 velocity vectors covering the entire SNR. Results. These exhaustive three-dimensional (3D) velocity measurements reveal the complex dynamics of Tycho’s SNR. Our study sheds light on a patchy Vz map, where most regions are dominated by the foreground or the background part of the shell. On a large scale, an asymmetry is seen, with the north being dominantly blueshifted and the south redshifted. The proper-motion vector field, Vxy, highlights different dynamics between the eastern and the western parts of the SNR. The eastern velocity field is more disturbed by external inhomogeneities and the south-east ejecta knot. In particular, a slow-down is observed in the north-east, which could be due to the interaction with higher densities, as seen in other wavelengths. The vector field is also used to backtrace the center of the explosion, which is then compared with potential stellar progenitors in the area. The latest Gaia DR3 parallax measurements exclude most stellar candidates based on their distances, leaving only stars B and E as possible candidates, at respective distances of 2.53−0.20+0.23 kpc and 3.52−1.0+2.0 kpc, which are consistent with the expected distance range of the SNR at 2.5–4 kpc.

Polarization of Intrabinary Shock Emission in Spider Pulsars

In so-called spider pulsars, the X-ray band is dominated by intrabinary shock (IBS) synchrotron emission. While the double-peaked X-ray light curves from these shocks have been well characterized in several spider systems (both black widows and redbacks), the polarization of this emission is yet to be studied. Motivated by the new polarization capability of the Imaging X-ray Polarization Explorer and the confirmation of highly ordered magnetic fields in pulsar wind nebulae, we model the IBS polarization by employing two potential magnetic field configurations: toroidal magnetic fields imposed by the preshock pulsar wind, and tangential shock-generated fields that follow the postshock flow. We find that if IBSs host ordered magnetic fields, the synchrotron X-rays from spider binaries can display a high degree of polarization (≳50%), while the variation in polarization angle provides a good probe of the binary geometry and the magnetic field structure. Our results encourage observational polarization studies of spider pulsars that can distinguish the proposed magnetic models and that constrain the unique properties of these systems better.

Soft X-ray emission from warm gas in IllustrisTNG circum-cluster environments

Context. Whereas X-ray clusters are extensively used for cosmology, their idealised modelling, through the hypotheses of spherical symmetry and hydrostatic equilibrium, is being questioned more and more. The soft X-ray emission detected in tens of clusters with ROSAT was found to be higher than what was expected from the idealised hot gas modelling, pointing to our incomplete understanding of these objects. Aims. Given that cluster environments are at the interface between the hot intra-cluster medium (ICM), warm circum-galactic medium (WCGM), and warm-hot intergalactic medium (WHIM), we aim to explore the relative soft X-ray emission of different gas phases in circum-cluster environments. Method. By using the most massive halos in IllustrisTNG at z = 0, we have predicted the hydrodynamical properties of the gas from cluster centres to their outskirts (5 R200), and modelled their X-ray radiation for various plasma phases. Results. First, we found that the radial profile of temperature, density, metallicity and clumpiness of the ICM are in good agreement with recent X-ray observations of clusters. Secondly, we have developed a method to predict the radial profile of soft X-ray emission in different bands, the column density of ions, and the X-ray absorption lines (O VIII, O VII, Ne IX, and Ne IX) of warm-hot gas inside and around clusters. Conclusion. The warm gas (in the form of both WCGM and WHIM gas) is a strong emitter in soft X-ray bands and is qualitatively consistent with the observational measurements. Our results suggest that the cluster soft excess is induced by the thermal emission of warm gas in the circum-cluster environments.

Impact of Non-Thermal Particle Acceleration on Radiative Signatures of AGN Jet-Cloud Interactions

This study investigates the complex dynamics of AGN (Active Galactic Nucleus) jet-cloud interactions, particularly focusing on the impact of non-thermal particle acceleration on the resulting radiative signatures. We utilize advanced computational simulations, tracking changes in jet properties and emissions over a span of 0.2 Myr (millions of years). The research design incorporates the modeling of jet-cloud interactions, with a key focus on variations in the jet's density, velocity, and magnetic field. Findings reveal a two-fold increase in the magnetic field strength up to ~5 μG due to cloud incorporation, which, coupled with an elevated non-thermal particle population, enhances synchrotron emissions, shifting the spectral index from 2.2 to 2.4. Inverse Compton scattering saw a 30% increase within the first 0.125 Myr, reflecting in an abrupt X-ray and gamma-ray emissions spike. Furthermore, the jet's light curve flux variability in the X-ray band showcased an initial peak increase of about 28% by 0.175 Myr, settling to a 20% increase by 0.2 Myr, attributable to cloud disruption and absorption. Conclusions drawn from these findings confirm our hypothesis that non-thermal particle acceleration dramatically influences the radiative signatures of AGN jet-cloud interactions .It underscores the necessity of considering such acceleration processes in modeling AGN jet-cloud interactions and posits that these changes could be instrumental as observational indicators, thereby contributing to more accurate interpretations of AGN activity and evolution.

A Chandra survey of Milky Way globular clusters – IV. Periodic X-ray sources

ABSTRACT We present a systematic search for periodic X-ray sources in 10 Galactic globular clusters (GCs) utilizing deep archival Chandra observations. By applying the Gregory–Loredo algorithm, we detect 28 periodic signals among 27 independent X-ray sources in 6 GCs, which include 21 newly discovered ones in the X-ray band. The remaining 4 GCs exhibit no periodic X-ray sources, mainly due to a relatively lower sensitivity of the data. Through analysis of their X-ray timing and spectral properties, complemented with available optical and ultraviolet information, we identify 21 of these periodic sources as cataclysmic variables (CVs). Combining with 11 periodic CVs in 47 Tuc similarly identified in the X-ray band, we compile the most comprehensive sample to date of GC CVs with a probable orbital period. The scarcity of old, short-period CVs in GCs compared to the Galactic inner bulge and solar neighbourhood, can be attributed to both a selection effect favouring younger, dynamically formed systems and the hindrance of CV formation through primordial binary evolution by stellar dynamical interactions common to the GC environment. Additionally, we identify a significant fraction of the GC CVs, most with an orbital period below or within the CV period gap, as probable magnetic CVs, but in the meantime there is a deficiency of luminous intermediate polars in the GC sample compared to the solar neighbourhood.

Investigation of optoelectronic properties of AgSbI4 using machine learning and first principles methods

Lead-free metal halides have potential uses in photovoltaic and other optoelectronic applications. AgSbI4 is an example of a lead-free metal halide that has recently been synthesized but not yet fully treated with theoretical calculations due to the large degree of site disorder in its cation sublattice. We employ a machine learning model of the total energy in AgSbI4 to choose a few simulation cells out of ∼107 possibilities; a task out of reach for current first principles methods. We calculate the structural and optoelectronic properties such as X-ray diffraction patterns and band gaps of these cells and find that they agree well with existing experimental data. Additionally, new predictions of the optoelectronic properties indicate that AgSbI4 may be a good choice for use as an absorber layer in tandem photovoltaic cells.

Testing theories of accretion and gravity with super-extremal Kerr discs

ABSTRACT Fitting the thermal continuum emission of accreting black holes observed across X-ray bands represents one of the principle means of constraining the properties (mass and spin) of astrophysical black holes. Recent ‘continuum fitting’ studies of Galactic X-ray binaries in the soft state have found best-fitting dimensionless spin values which run into the prior bounds placed on traditional models (a⋆ = 0.9999). It is of critical importance that these results are robust, and not a result solely of the presence of these prior bounds and deficiencies in conventional models of accretion. Motivated by these results we derive and present superkerr, an xspec model comprising of a thin accretion disc solution valid in the Kerr geometry for arbitrary spin parameter a⋆, extending previous models valid only for black holes (|a⋆| < 1). This extension into ‘super-extremal’ space–times with |a⋆| > 1 includes solutions which describe discs evolving around naked singularities, not black holes. While being valid solutions of Einstein’s field equations these naked singularities are not expected to be present in nature. We discuss how the ‘measurement’ of a Kerr spin parameter 1 < a⋆ < 5/3 would present compelling evidence for the requirement of a rethink in either standard accretion theory, or our theories of gravity.

Detection of X-ray/UV delay in NGC 4051 using AstroSat observations

ABSTRACT We study the connection between the variations in the far-ultraviolet (FUV), near-ultraviolet (NUV), and X-ray band emission from NGC 4051 using 4 d long AstroSat observations performed during 5–9 June 2016. NGC 4051 showed rapid variability in all three bands with the strongest variability amplitude in the X-ray band ($F_{\mathrm{ var}} \sim 37~{{\ \rm per\ cent}}$) and much weaker variability in the UV bands ($F_{\mathrm{ var}} \sim 3{\!-\!}5~{{\ \rm per\ cent}}$). Cross-correlation analysis performed using interpolated cross-correlation functions and discrete cross-correlation functions revealed a robust correlation (∼0.75) between the UV and X-ray light curves. The variations in the X-ray band are found to lead those in the FUV and NUV bands by ∼7.4 ks and ∼24.2 ks, respectively. The UV lags favour the thermal disc reprocessing model. The FUV and NUV bands are strongly correlated (∼0.9) and the variations in the FUV band lead those in the NUV band by ∼13 ks. Comparison of the UV lags found using the AstroSat observations with those reported earlier and the theoretical model for thermal reverberation timelag suggests a possible change in either the geometry of the accretion disc/corona or the height of the corona.

Multiwavelength analysis of Fermi-LAT blazars with high-significance periodicity: detection of a long-term rising emission in PG 1553+113

ABSTRACT Blazars display variable emission across the entire electromagnetic spectrum, with time-scales that can range from a few minutes to several years. Our recent work has shown that a sample of five blazars exhibit hints of periodicity with a global significance ${\gtrsim}2\, \sigma$ at γ-ray energies, in the range of 0.1 GeV < E < 800 GeV. In this work, we study their multiwavelength emission, covering the X-ray, ultraviolet, optical, and radio bands. We show that three of these blazars present similar periodic patterns in the optical and radio bands. Additionally, fluxes in the different bands of the five blazars are correlated, suggesting a co-spatial origin. Moreover, we detect a long-term (≈10 yr) rising trend in the light curves of PG 1553+113, and we use it to infer possible constraints on the binary black hole hypothesis.

Observing gravitational redshift with X-ray emission in galaxy clusters withAthenaX-IFU

Context.The Doppler shift predicted by general relativity for light escaping a gravitational potential has been observed on Earth as well as in the direction of various stars and galaxy clusters at optical wavelengths.Aims.Observing the gravitational redshift in the X-ray band within galaxy clusters could provide information on their properties and, in particular, their gravitational potential. We present a feasibility study of such a measurement, using the capabilities of the next-generation European X-ray observatoryAthena.Methods.We used a simple generalized Navarro–Frenk–White potential model along with aβ-model for the density of baryonic matter, which sets the emission to provide an estimation of the observed redshift in the simplest of cases. We generated mock observations with theAthenaX-ray Integral Field Unit (X-IFU) for a nearby massive cluster, while seeking to recover the gravitational redshift along with other properties of the toy model cluster.Results.We investigated the observability of the gravitational redshift in an idealized test case of a nearby massive cluster with theAthenaX-IFU instrument, as well as its use in probing the properties of the potential well. We were also able to constrain the mass to a ∼20% level of precision and the cosmological redshift to less than ∼1%, within a simplified and idealized observational framework. More refined simulations accounting for further effects such as the internal gas motions and the actual shape of the potential well are required to fully investigate the feasibility of measuring the gravitational redshift for a single target or statistically over a sample of galaxy clusters.

The Galactic supernova remnant CTB 1: optical and X-ray emission analysis

ABSTRACT We present the kinematic results for the supernova remnant (SNR) CTB 1, obtained with the PUMA equipment of the 2.1-m telescope at San Pedro Mártir National Astronomical Observatory, Baja California, Mexico. The observations were made on the H α line using a Fabry–Perot interferometer. The kinematics derived from the Fabry–Perot velocity cubes allowed us to estimate a kinematic distance for this SNR. We estimate that CTB1 is about 3.8 kpc from the sun, corresponding to a linear diameter of 19 pc, with an expansion velocity of $286 \rm ~ km ~s^{-1}$. Additionally, we analyse the diffuse X-ray emission from CTB 1 using data from the XMM–Newton observatory. From the best fits to the spectrum of southwest and northeast regions, we obtained a hot plasma temperature $\sim 0.1-0.3 ~\rm keV$ with an overabundance in O and Ne and a lower abundance in Fe, which could be caused by a SNR with a stellar progenitor between 10 to $70 \, \rm {\rm M}_{\odot }$. The initial energy of the supernova explosion is estimated between (0.6–1.0) × 1050 erg for soft X-ray emission. The X-ray emission also presents a non-thermal component of low surface brightness in the hard X-ray band. Images in radio and X-ray emission allow us to classify CTB 1 as mixed-morphology supernova type. The evolution models show that the cloudy ISM model is the only one that reproduces the mixed morphology type observed in the SNR CTB 1.