Recovering Thermodynamics from Spectral Profiles Observed by IRIS. (II). Improved Calculation of the Uncertainties Based on Monte Carlo Experiments by Alberto Sainz Dalda, Bart De Pontieu

“…Observations by the Interface Region Imaging Spectrograph (IRIS) of the Mg ii h & k spectral lines have provided a new diagnostic window toward knowledge of the complex physical conditions in the solar chromosphere. …”
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IRIS2+: A Comprehensive Database of Stratified Thermodynamic Models in the Low Solar Atmosphere by Alberto Sainz Dalda, Aaryan Agrawal, Bart De Pontieu, Milan Gošić

“…The latter result from inverting the observed RPs, which are the result of clustering multiline spectral profiles observed by the Interface Region Imaging Spectrograph in 126 active regions (ARs). …”
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Constraining the Systematics of (Acoustic) Wave Heating Estimates in the Solar Chromosphere by Momchil E. Molnar, Kevin P. Reardon, Steven R. Cranmer, Adam F. Kowalski, Ivan Milić

“…Sit-and-stare observations taken with the Interface Region Imaging Spectrograph and data from the Interferometric BIdimensional Spectrograph were used to provide the observational basis of this work. …”
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Signatures of red-shifted foot points in the quiescent coronal loop system by Y. K. Rao, A. K. Srivastava, P. Kayshap, B. N. Dwivedi

“…The flows at the foot points of such loop systems are studied using spectral data from the Interface Region Imaging Spectrograph (IRIS). The Doppler velocity distributions at the foot points lying in the moss region show the negligible or small flows at the Ni I, Mg II k3, and C II line corresponding to upper photospheric and chromospheric emissions. …”
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Chromospheric thermodynamic conditions from inversions of complex Mg II h & k profiles observed in flares by Alberto Sainz Dalda, Alberto Sainz Dalda, Bart De Pontieu, Bart De Pontieu, Bart De Pontieu

“…The former have mainly focused on the corona, while the latter have mostly been used to investigate the conditions in the chromosphere and photosphere. The Interface Region Imaging Spectrograph (IRIS) instrument has served as a gateway between these two cases, given its capability to observe quasi-simultaneously the corona, the transition region, and the chromosphere using different spectral lines in the near- and far-ultraviolet ranges. …”
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Sustained Heating of the Chromosphere and Transition Region Over a Sunspot Light Bridge by Rohan E. Louis, Shibu K. Mathew, A. Raja Bayanna, Christian Beck, Debi P. Choudhary

“…In contrast, we use here data from the Multi-Application Solar Telescope (MAST), the Interface Region Imaging Spectrograph (IRIS), Hinode, the Atmospheric Imaging Assembly (AIA), and the Helioseismic and Magnetic Imager (HMI) to analyze the sustained heating over days in an LB in a regular sunspot. …”
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Photospheric and Chromospheric Magnetic Field Evolution during the X1.6 Flare in Active Region NOAA 12192 by F. Ferrente, F. Zuccarello, S. L. Guglielmino, S. Criscuoli, P. Romano

“…The nonlinear force-free field extrapolations, together with the analysis of the ribbons’ isophotes obtained from Interface Region Imaging Spectrograph data, suggest that the region corresponding to the magnetic intrusion observed by IBIS is characterized by a complex magnetic connectivity and is almost cospatial with the area affected by the initial energy release.…”
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Origin of Quasi-periodic Pulsation at the Base of a Kink-unstable Jet by Sudheer K. Mishra, Kartika Sangal, Pradeep Kayshap, Petr Jelínek, A. K. Srivastava, S. P. Rajaguru

“…We studied a blowout jet that occurred at the west limb of the Sun on 2014 August 29 using high-resolution imaging/spectroscopic observations provided by the Solar Dynamics Observatory/Atmospheric Imaging Assembly and the Interface Region Imaging Spectrograph. An inverse γ -shaped flux rope appeared before the jet–morphological indication of the onset of kink instability. …”
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Magnetic Fields and Plasma Heating in the Sun’s Atmosphere by P. Judge, L. Kleint, R. Casini, A. G. de Wijn, T. Schad, A. Tritschler

“…Data from the Solar Dynamics Observatory and Interface Region Imaging Spectrograph are combined to ask: Why is only a fraction of emerging flux filled with heated plasma? …”
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A Statistical Study of IRIS Observational Signatures of Nanoflares and Nonthermal Particles by Kyuhyoun Cho, Paola Testa, Bart De Pontieu, Vanessa Polito

“…We conduct a statistical study on the response of the chromosphere and transition region to nanoflares, as observed by the Interface Region Imaging Spectrograph (IRIS), by using an algorithm for the automatic detection of these events. …”
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Nonthermal Motions and Atmospheric Heating of Cool Stars by S. Boro Saikia, T. Lueftinger, V. S. Airapetian, T. Ayres, M. Bartel, M. Guedel, M. Jin, K. G. Kislyakova, P. Testa

“…We investigate whether nonthermal motions in cool stars exhibit the same behavior as on the Sun by analyzing archival stellar spectra taken by the Hubble Space Telescope, and full-disk Solar spectra taken by the Interface Region Imaging Spectrograph. We determined the nonthermal velocities by measuring the excess broadening in optically thin emission lines formed in the stellar atmosphere; the chromosphere, the transition region, and the corona. …”
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Observations of Magnetic Reconnection and Particle Acceleration Locations in Solar Coronal Jets by Yixian Zhang, Sophie Musset, Lindsay Glesener, Navdeep K. Panesar, Gregory D. Fleishman

“…We present a multiwavelength analysis of two flare-related jets on 2014 November 13, using data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA), the Reuven High Energy Solar Spectroscopic Imager (RHESSI), the Hinode/X-ray Telescope (XRT), and the Interface Region Imaging Spectrograph (IRIS). Unlike most coronal jets, where hard X-ray (HXR) emissions are usually observed near the jet base, in these events HXR emissions are found at several locations, including in the corona. …”
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Reconnection-generated Plasma Flows in the Quasi-separatrix Layer in Localized Solar Corona by Sripan Mondal, Abhishek K. Srivastava, Sudheer K. Mishra, K. Sangal, Pradeep Kayshap, Yang Guo, David I Pontin, Vadim M. Uritsky, Leon Ofman, Tongjiang Wang, Ding Yuan

“…In addition, spectroscopic analysis of Interface Region Imaging Spectrograph Si iv λ 1393.77 line profiles show a rise of line width in the same time range depicting the presence of mass motion in the observed cusp-shaped region. …”
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Spicules in IRIS Mg ii Observations: Automated Identification by Vicki L. Herde, Phillip C. Chamberlin, Don Schmit, Souvik Bose, Adrian Daw, Ryan O. Milligan, Vanessa Polito

“…Using this algorithm we identify 2021 events in three Interface Region Imaging Spectrograph (IRIS) data sets with unique solar feature targets spanning a total of 300 minutes: (1) active region, (2) decayed active region/active network, and (3) coronal hole. …”
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Are Quasi-periodic Pulsations Independent of Loop Oscillations in Solar Flare? by Fanpeng Shi, Dong Li, Zongjun Ning, Yangfan Guo, Song Feng, Jun Xu

“…However, almost immediately after QPPs, a minority of flare loops display their Doppler velocity oscillations with a significant period of ∼4 minutes, which are observed by the Interface Region Imaging Spectrograph at the coronal line Fe xxi 1354.08 Å ( T ∼ 10 ^7 K), while its intensity and width show no similar oscillation. …”
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Splitting and Reconstruction of a Solar Filament Caused by Magnetic Emergence and Reconnection by Zhike Xue, Xiaoli Yan, Jincheng Wang, Liheng Yang, Zhe Xu, Yang Peng, Qiaoling Li

“…We present observations and interpretation of a nonerupting filament in NOAA active region (AR) 12827 that undergoes splitting and restructuring on 2021 June 4, using the high-resolution data obtained by the New Vacuum Solar Telescope, the Solar Dynamics Observatory, and the Interface Region Imaging Spectrograph. At the beginning, the right footpoint of the filament is rooted in the AR positive polarity, and its right leg has a spread-out structure, which is confirmed by the extrapolated 3D magnetic structure. …”
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Macrospicules and Their Connection to Magnetic Reconnection in the Lower Solar Atmosphere by Yadan Duan, Yuandeng Shen, Hechao Chen, Zehao Tang, Chenrui Zhou, Xinping Zhou, Song Tan

“…The spectral diagnosis from the Interface Region Imaging Spectrograph at one of BPs reveals signatures of reconnection at the lower atmosphere. …”
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Deciphering Solar Coronal Heating: Energizing Small-scale Loops through Surface Convection by D. Nóbrega-Siverio, F. Moreno-Insertis, K. Galsgaard, K. Krikova, L. Rouppe van der Voort, R. Joshi, M. S. Madjarska

“…Additionally, we provide synthetic observables to be compared with Hinode, Solar Orbiter, and the Interface Region Imaging Spectrograph (IRIS). Our results constitute a step forward in the understanding of the many different facets of the solar coronal heating problem.…”
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Chromospheric Heating from Local Magnetic Growth and Ambipolar Diffusion under Nonequilibrium Conditions by Juan Martínez-Sykora, Jaime de la Cruz Rodríguez, Milan Gošić, Alberto Sainz Dalda, Viggo H. Hansteen, Bart De Pontieu

“…In the present study, we tackle this old problem by using a very-high-spatial-resolution simulation of quiet-Sun conditions performed with radiative MHD numerical models and interface region imaging spectrograph (IRIS) observations. We have expanded a previously existing 3D radiative MHD numerical model of the solar atmosphere, which included self-consistently locally driven magnetic amplification in the chromosphere, by adding ambipolar diffusion and time-dependent nonequilibrium hydrogen ionization to the model. …”
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Extreme Red-wing Enhancements of UV Lines during the 2022 March 30 X1.3 Solar Flare by Yan Xu, Graham S. Kerr, Vanessa Polito, Nengyi Huang, Ju Jing, Haimin Wang

“…Within a ∼41 s period (17:34:48 UT to 17:35:29 UT), Interface Region Imaging Spectrograph observations show spectral lines of Mg ii , C ii , and Si iv with extremely broadened, asymmetric red wings. …”
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