GRB 130427A Afterglow: a Test for GRB Models

Physics & Astronomy Faculty Publications Physics and Astronomy

2-1-2018

GRB 130427A Afterglow: A Test for GRB Models

Massimiliano De Pasquale Istanbul University, [email protected]

M. J. Page University College London

D. A. Kann Instituto de Astrofisica de Andalucia (CISC)

S. R. Oates University of Warwick

S. Schulze Weizmann Institute of Science

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Repository Citation De Pasquale, M., Page, M. J., Kann, D. A., Oates, S. R., Schulze, S., Zhang, B., Cano, Z., Gendre, B., Malesani, D., Rossi, A., Gehrels, N., Troja, E., Piro, L., Boër M., Stratta, G. (2018). GRB 130427A Afterglow: A Test for GRB Models. Proceedings of Science 1-8. http://dx.doi.org/10.22323/1.306.0071

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This Conference Proceeding has been accepted for inclusion in Physics & Astronomy Faculty Publications by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. Authors Massimiliano De Pasquale, M. J. Page, D. A. Kann, S. R. Oates, S. Schulze, Bing Zhang, Z. Cano, B. Gendre, D. Malesani, A. Rossi, N. Gehrels, E. Troja, L. Piro, M. Boër, and G. Stratta

This conference proceeding is available at Digital Scholarship@UNLV: https://digitalscholarship.unlv.edu/ physastr_fac_articles/148 PoS(MULTIF2017)071 https://pos.sissa.it/ ∗† [email protected] Copyright owned by the author(s) under the terms of the Creative Commons c Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). Massimiliano De Pasquale Department of Astronomy and Space Sciences,Turkey Istanbul University, Beyazıt, 34119, Istanbul, E-mail: M. J. Page Mullard Space Science Laboratory, University CollegeKingdom London, Dorking RH56NT, United D. A. Kann Istituto de Astrofisica de Andalucia (CSIC), Glorieta de Astronomia, E-18008 Granada, Spain S. R. Oates Department of Physics, University of Warwick, Coventry, CV4 7AL, UK S. Schulze Department of Particle Physics and Astrophysics,7610001, Weizmann Institute Israel of Science, Rehovot B. Zhang Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154, USA Z. Cano Instituto de Astrofisica de Andalucia (CSIC), Glorieta de Astronomia, E-18008 Granada, Spain B. Gendre University of Virgin Islands, 2 JohnObservatory, BrewerÕs St Bay, St Thomas, Thomas, VI VI 00802, 00802, USA USA; Etelman D. Malesani Dark Cosmology Centre, Niels Bohr Institutet,DK-2100 University Copenhagen of Denmark Copenhagen, Juliane Maries Vej 30, A. Rossi Istituto Astrofisica Spaziale e Fisica CosmicaBologna, di Italy Bologna (INAF), Via P. Gobetti 101, I-40129 GRB 130427A afterglow: a test for GRB models PoS(MULTIF2017)071 . detected the afterglow of this event Athena Chandra and XMM-Newton erg and redshift of 0.34, it combined a very high energy release with a relative 53 10 × 5 . 31 over more than three decades in time. . 1 = Speaker. A footnote may follow. Gamma-ray Burst 130427A had the largestoutput fluence of for 8 almost 30 years. With an isotropic energy proximity to Earth in an unprecedentedSensitive fashion. X-ray facilities such as for a record-breaking baseline of 90event Ms. over We such show an the interval. X-rayα light The curve light of curve GRB shows 130427A an of unbroken this In power law this decay presentation, with a we slopeto investigate of interpret the GRB consequences 130427A of and thisopening the angle, result implications energetics, for in surrounding the the medium). context scenariosafterglow We observations of also proposed for remark the several the forward hundreds chance of shock of Ms model with extending (jet GRB † ∗ N. Gehrels, E. Troja NASA Goddard Space Flight Center, Greenbelt, Maryland, MD 20771, USA L. Piro IAPS-INAF, Via Fosso del Cavaliere 100, 00133, Rome, Italy M. Boër CNRS-ARTEMIS, Boulevard de lÕObservatoire, CS 34229, F-06304 Nice Cedex 4, France G. Stratta Department of Physics, University of Urbino, V. S. Chiara 27, I-61029 Urbino, Italy XII Multifrequency Behaviour of High Energy12-17 Cosmic June, Sources 2017 Workshop Palermo, Italy PoS(MULTIF2017)071 t 34. . 0 and XMM ν = z observations , fits the data α − t ∝ F , and the density and Chandra p X-ray Telescope (XRT; Massimiliano De Pasquale is the flux density, ν Swift 007. Power law models with F . 0 ± 312 , where . α 1 − -ray band within few hundreds seconds. t = γ β erg (Perley et al. 2014) at redshift − α ν . XRT observed GRB 130427A until October . When analyzing the light-curve, we consider 53 1 4% of them occur at lower redshift. Thus, GRB ∝ 10 1 ν . F × 5 erg in the . 8 Chandra 55 , and . = , the fraction of energy in radiating electrons and magnetic x 10 iso , and K γ iso , 10 E ∼ 68. The best fit 90Ms after the trigger, led to a significant detection. These are E γ / × E 3 ' . N 79 = x = . N f . o XMM-Newton . carried out observations in May, June and December 2013, in May and De- d / 2 χ , the index of the power law energy distribution of electrons observations, taken B ε 3% of GRBs have a larger and XMM-Newton e . ε -ray band this burst released The standard FS model predicts phenomena occurring over long time scales in GRB after- Gamma-ray Bursts (GRBs) are the brightest explosions in the Universe (Kumar & Zhang Our dataset is constituted by X-ray observations carried out by Chandra γ 3. Discussion glows. Some of them are: one or more breaks do not yield significant improvements to the fit. adequately, with only observations taken after 47with ks, the because proposed we scenarios. are We find interested that in a the simple consistency power of law model, late i.e. time flux data They are followed by the so-calledthe “afterglow", whole which electromagnetic is a spectrum. slowlyterglow fading The emission is most detected popular the across theoretical so modelultrarelativistic called used ejecta "forward to of shock" explain the (FS; explosion thewave drive af- Sari, a accelerates Piran shockwave the in & electrons the Narayan of circumburstradiation. the 1998). medium; medium The this which, FS shock- In model in thisrameters, predicts turn, model, namely the re-emits the the flux kinetic the energy at energyfield any as wavelength synchrotron and epochs on the basis of few pa- 2015), being able to release up to GRB 130427A afterglow: a test for GRB models 1. Introduction profile of the circumburst medium. Byexplained investigating by the the afterglow, FS we model can and check whetherwith the whether GRB parameters it 130427A, inferred can the are be realistic. event withthe In this the article, largest we fluence deal in theOnly last 29 years. Assuming130427A isotropy, in represents an unique chancetail. to In study the a following, veryare we bright frequency use and event the time and convention since test triggerotherwise the specified, respectively. while FS Errors are model at in 68% de- confidence level (CL), unless 2. Observations and Results Burrows et al. 2005), 2013. cember 2015 (PIs: De Pasquale,(PI: Boer). Fruchter) Further, taken we in used February publiclyand and available June 2014, January 2015,the January latest 2016. known detections Even of the an last of X-ray the afterglow data of a were cosmological carriedlight-curve GRB. out of Reduction as and GRB described analysis 130427A in is De shown Pasquale in et Figure al. (2016). The derived 90 Ms X-ray PoS(MULTIF2017)071 , jet θ of the ∼ Γ 1 − Γ Massimiliano De Pasquale 2 is the semi-opening angle of the ejecta, the observer will see the entire emitting surface GRB 130427A X-ray afterglow over 90 Ms. The solid line shows our best fit model. Adapted jet θ ; this phenomenon is interpreted as presence of collimated ejecta. The Lorentz factor p - Jet break (Zhang & MacFadyen 2009) i.e. a steepening of the light curve down to a slope However, these phenomena will show up differently in the afterglow light curves depending - Change of physical parameters of the shock emission. There is no reason to think that, over a - Change of the density profile of the circumburst medium. Long GRBs like 130427A are ' α on the environment. In thismodeling respect, of GRB different 130427A groups afterglow. have Laskar et adopted al. different (2013; environments henceforth in L13) their and Perley et al. (2014; Figure 1: from De Pasquale et al. (2016) long period of time and substantialmay changes not of evolve. the dimension of the ejecta, the physical parameters linked to the demise of massive stars.that These the objects produce GRB strong ejecta stellar winds; will thusthey initially it will is move eventually expected reach into a an distance environment at with which wind a medium density of profile. constant density However, profile is present. ejecta is supposed to decrease inwhere time because these sweep circumbustand medium. no When further radiation previously beamedof away will the be afterglow detected. light-curve. This feature causes a steep drop GRB 130427A afterglow: a test for GRB models PoS(MULTIF2017)071 . 3 3 as − r ' is the ˙ 1 cm M > ∼ 4. L13 and / 3 to find a lower , we find upper − 1 p R 3.1 4 / 3 = , as is assumed by both Massimiliano De Pasquale c decreases with radius α ν ρ respectively. Finally, Maselli et 7 . 1 − pc (3.1) pc (Fryer et al. 2006), where 2 Ar / 1 2 , 1 6 , we can use equation − 0 t = 1 n 2 1 / 3 9. However, we derive a 95% lower limit of ρ − 1 / . 1 0 ?, − 5 A 57 pc for P14 and L13, respectively. The radius and = − 54 1, the previous lower limits on ˙ , 3 4 and cooling frequency . These densities are unrealistic, because they are . M α > 3 1 2 = iso 1 , m − / − ' 5 1 K ν R 1 − E Ar cm ˙ R 8 M . 4 = 4 − is contained within a region of shocked stellar wind where reached by the ejecta will be is the wind density normalization for a mass loss rate of is 0.3 and 0.07 for P14 and L13 respectively. ρ 1 = ? R 54 10 , R A R iso × , 9 of GRB 130427A X-ray light-curve. Knowing this limit and the K 6 120 pc and . is the density of the pre-existing material in which the stellar wind E 0 0 < OB stars could produce “super blubbles" in which density decreases > n = 0 4 1 n R α 10 and 1 ∼ and − 4 yr − stellar wind

2, thus the predicted slope is 100 pc. However, even the most massive star clusters in the Local Group may . 2 10 2 M − ∼ × r for the progenitor of the GRB, and the pedex “iso" means that we are considering ' 5 1 . and kinetic energy derived by L13 and P14 p − for 1 ? . We determine 2 1 003 in both articles, while yr . Kouveliotou et al. (2013; K13) and van der Horst et al. (2014,V14) have settled on A . < 2 − R 0

r 0 − ˙ n = M ' Ar (Chevalier & Li 2000) where A In a free wind region, the radius 5 1 ρ − = 10 isotropic energy. According to the standard picture ofregion a of stellar free wind bubble stellar (Weaver et wind al. ofdensity 1977), radius is the constant. Thus, the expandingWhen ejecta this will happens, unavoidably have the to FS enter model intois predicts the between a latter change region. the in synchrotron afterglow decay peak slope frequency if the observing band L13 and P14. In an ISMP14 environment, assume the decay slope is63 expected Ms to for be any flattening to values of bubble was blown. Assuming a standard as not contain so many massive starsis (Beck not 2015). located We outside also the note opticalionisation that image lines the of of afterglow of its the GRB host optical 130427A galaxycomm.). spectrum (Levan show Thus, et no it al. signature is 2014). of unlikelyin galactic that Moreover, a the winds the very low- (Khrühler burst large occurred et wind in environment al., extending a priv. above low the density galactic extragalactic disk. environment, or mass loss rate in limits too low for star forming regions whereHII the region massive surveys progenitors (Hunt of & GRBs Hirashita areAccording 2009, expected to Peimbert to be & located. Peimbert the 2013) numerical yieldclusters densities simulations with more of than Sharma et al. (2014) and Yadav et al. (2016), star 3.1 Models in al. 2014 (M14) have assumed athese constant authors density have medium modeled (as the in afterglowWe the emission will interstellar with test medium; data ISM). whether up All their toyears. modeling a few can months still after hold the and trigger. explain the X-ray data extending for limit on of the free stellar wind region is given by GRB 130427A afterglow: a test for GRB models P14) have assumed a free stellarρ wind environment, in which density a non-standard stellar wind, in which PoS(MULTIF2017)071 2 X = / ν 03, e . 2 ε jet 0 θ 3 even . ± = 1 , while in b 79 34 and X- f , where ' . β . c 0 2 2 ν α / 170 pc. Thus, . This density = 3 = . The next step > 3, the so-called 6 . > p σ / ∼ β 1 = X 5 − ν . R , where with the formula α 2 b f 2 which would occur for jet ' and θ < × g cm at 20 pc from the explo- c Massimiliano De Pasquale ) p 007 and ν 3 3 . − iso − 0 , < is the fraction of accelerated, K 10 ± X cm E ξ ν 7 ' + − 312 A . iso 1 10 , 2 Ms after the trigger, while our data γ . = ∼ E 4 , where 8 . , evolve with time in a different fashion is satisfied within α ' 0 B = ( c − erg and ε ν ) corr 54 < , 2d and / tot X 10 t e ν E ε 4 ' = ( is not supposed to be larger than 1 ξ iso e , ε , K 5 90 Ms, and it not clear why we would be accelerating . Since we find . 2. The above expression is valid for E 2 0 / ) 8 ' 1 / ) 8d − . 5 β 0 2 / + t / ( 3 001 at β . 3 × = 0 5 α . We modeled the X-ray afterglow imposing the conditions above and ' − = ( is not satisfied, while c . It is possible to derive or constrain the value of c ν ξ 10 α ν jet θ = > we find. and B X β ε m ν , ν 6 . 0 ) 8d . 2 the expression is 0 > 20 times as long. The parameter / t p ( ' for the value of 5 Ms. Moreover, . × c 4 ν For K13 assumptions are pure synchrotron emission (i.e. no inverse Compton), V14 scenario presumes a two-component jet with a narrow and a wide component. The after- Could the FS model, in the basic ISM form, explain the behaviour of GRB 130427A X-ray M14 scenario consists of constant density medium and an early jet break at 37 ks. After jet 2 > ' 027 . X ν normalization value implies a very thin wind, with densities is the frequency of the X-ray band,the and latter spherical we expansion. should In have the former case, glow is the sum ofrange the and emission that of the the physical two parameters, components. such as V14 assumes parameters within a wide afterglow? To answer thisThe question, FS we scenario predicts can relationsobserving first frequency, between take the these medium a density two look profile, indicesthe and at case that the of the kind depend X-ray of decay emission on expansion, of and GRB the jetted 130427A, or spectral position the spherical. relevant indices. of cases In the are GRB 130427A afterglow: a test for GRB models 3.2 Models in non-standard wind environs sion site. As in theeven the previous scenario scenario, proposed we by needmaterial. K13 a runs very into big the stellar problem wind of radius, a too low density of the pre-existing 0 emitting electrons. With this evolution, the decay slope of the X-ray afterglow can be only such a tiny fractionparameters of and electrons. early jet Overall, break is we weakened conclude by that our the new3.4 dataset. ISM scenario A with basic ISM evolving scenario? the relation for the to check whether this FSThe total model energy is corrected viable for beaming isis effects examine the is “beaming the factor" required that parameters, takesan especially semi-opening into angle account energy. the possibility that the ejecta are collimated within breaks, the decay slopes is supposed to be steep; however M14 postulates evolving parameters: depending on whether they characterizemodel the could indeed wide account or for the thecies late narrow of X-ray component. its data, but parameters; We it see believe may De that achieve Pasquale that this et by al. several indetermina- (2016)3.3 for more ISM details. model with early jet break and evolving parameters the observed X-ray flux and we derived ray band between in a post jet-break regime. However, M14extend used data up to “equipartition" value. With theat evolution assumed by M14, this value would be reached already PoS(MULTIF2017)071 × , 5 is . 6 erg. and 3.2 n > ∼ K 53 E mission 10 corr decreases , × tot 2 . corr E , 1 tot Athena > ∼ E We point out that corr , implies lower limits tot jet E t Massimiliano De Pasquale rad (3.2) 8 ; see Figure 2. / and on the ratio between 1 1 ; we made those assumptions that n − − s corr 007 till very late epochs; no jet break , 2 . . Thus, by means of the ESA flagship − 53 tot 0 , E iso ± n , K . Thus, the lower limit energy requirement is E and 3 erg cm 312 . 1 jet 8 16 θ 5 / observations of the afterglow of the exceptionally − is reduced, and as a consequence 3 = is the jet break time, expressed in days, and d jet α , z d θ , jet t + jet erg. Assumptions on t 1 , the lower limit on total energy corrected for beaming is 53 Chandra jet with respect to the jet axis, the steepening in the light curve θ . Thus, 10 12 4 . . obs and 0 × obs 0 θ θ 2 . = = 1 + jet jet ≥ obs θ θ θ corr , tot with erg. While this is still a rather large amount, it is half the value required in the E XMM-Newton jet 52 θ 10 × 5 . 6 62 Ms. After some algebra, we find that this lower limit on 47 rad and > . ∼ = 0 erg. To see the full derivation refer to De Pasquale et al. (2016). A variant of this scenario, which manages to reduce the energy requirement, is the off-axis (Zhang & MacFadyen 2009) where The worst case scenario for future observations of GRB 130427A X-ray afterglow is that a We presented We found that the simple, ISM scenario with on-axis observer requires jet corr ≥ t 3 , are required to calculate the lower limits on 100 days from the trigger and based on the standard, forward shock model for GRB afterglows. 52 γ tot jet the density of thefor environment. Fitting theθ X-ray light curve, we derive a 95% CL lower limit will be visible only when the observer sees emission from the “far end" of the outflow. In Eq. case. If the Earth is at an angle E minimize the value of the openingvery angle high; and in energy realistic conditions,produce a the black output. hole of a few tens of solar masses would be required to jet break occurs now. If that happened, the predicted flux at the launch of the as well. We find that for 10 (2028, Nandra et al. 2013) would be around 10 E simple on-axis case. Webands point other out, than however, the that X-ray this one. ISM scenario needs testing against data4. in Conclusions The scenarios in freemedium stellar which wind we are examined farwind (P14, too either L13) low involve require a for densities too starparameters low of forming (V14). density the regions. environment pre-existing The (K13) ISM asphysical The parameters, model well, scenarios but or proposed it in evolving is by and hard non-standard M14 to unconstrained stellar assumes keep the an decay early slow for jet 90 break Ms. with evolving GRB 130427A afterglow: a test for GRB models one must replace luminous GRB 130427A, whichfollow took up place for the up X-ray toshows afterglow a 90 of simple Ms power a law from cosmologicalor decay burst. the with other trigger. slope We changes found of that This slope∼ the is are flux detected. the of longest the We tested source the durability of scenarios built on data up to However, an off-axis variant of the same scenario could still explain observations with a source with this fluxX-ray would observatory, we still will be be detectable able by to Athena extend the time coverage of GRB 130427A by one order of PoS(MULTIF2017)071 9 ]. 10 mission. Athena 8 (2005) 165 10 Massimiliano De Pasquale 120 astro-ph/1412.0769 SSRv , 7 10 (2015) 1530002 [ 24 6 Time (s) 6 10 The Swift X-Ray Telescope IJMPD , GRB 130427A X−ray LC GRB 130427A 5 ]. 10

The youngest globular clusters

.10.1 0.01 10 10 10 10 10

10 10 −3 −4 −5 −6 −7

−8 GRB 130427A X-ray afterglow light curve extended to 2028 in the worst-case scenario for the 0.3−10 keV Flux *1e+9 Flux keV 0.3−10 astro-ph/0508.071 [ This work was supported by Scientific Research Project Coordination Unit of Istanbul Univer- [1] S. Beck, [2] D. Burrows, J. Nousek, J. Kennea, et al., flux (dashed blue line). At that epoch, the afterglow would still be detectable by the ESA Figure 2: sity, project number: BEK-2017-25641. References GRB 130427A afterglow: a test for GRB models magnitude. If we foundmodel we that have no highlighted change so far ofbe would abandoned. slope be has further exacerbated occurred to by the then, point that the this problems model should for the FS PoS(MULTIF2017)071 497 , ApJ 343 781 218 ApJL (2014) , ApJ (2009) 1327 ApJ ] , , 792 Science . 507 (2013) 119 (2015) 1 pJ GHz A , 16 776 561 A&A 10 , pJ ]. A Massimiliano De Pasquale PhR ]. , , ]. (2013) 89 (2016) 1111 778 462 astro-ph/1404.1945 ]. A&A , astro-ph/1306.2307 MNRAS ] , A comprehensive radio view of the extremely astro-ph/0902.2396 astro-ph/9908.272 (2014) 3151 [ astro-ph/1402.6695 7 uSTAR Observations of GRB 130427A Establish a The 80 Ms follow-up of the X-ray afterglow of GRB N 444 he Hot and Energetic Universe: A White Paper presenting RB 130427A: A Nearby Ordinary Monster, How multiple supernovae overlap to form superbubbles ] T G A Reverse Shock in GRB 130427A A Hubble Space Telescope Observations of the Afterglow, Interstellar bubbles. II - Structure and evolution ]. ] The Environments around Long-Duration Gamma-Ray Burst ]. The Afterglow of GRB 130427A from 1 to (2009) 1261 [ astro-ph/0604.432 (2005) 195 [ MNRAS In a hot bubble: why does superbubble feedback work, but isolated (2014) 3463 [ , ]. 698 Spectra and Light Curves of Gamma-Ray Burst Afterglows 536 443 ]. The Dynamics and Afterglow Radiation of Gamma-Ray Bursts. I. Densities, Temperatures, Pressures, and Abundances Derived from O II ]. ]. ]. ]. ApJ astro-ph/1603.00815 ApJ , , Wind Interaction Models for Gamma-Ray Burst Afterglows: The Case for The size-density relation of extragalactic H II regions The physics of gamma-ray bursts & relativistic jets (2006) 1269 [ MNRAS , 647 astro-ph/1311.5245 (2017) 1720 [ ApJ , astro-ph/1311.5254 astro-ph/1307.4401 astro-ph/9712.005 465 astro-ph/1307.5338 (2013) 1 [ astro-ph/1305.2453 astro-ph/1410.0679 astro-ph/1310.0089 astro-ph/0910.2804 astro-ph/1602.04158 115 [ (2014) 48 [ Supernova, and Host Galaxy Associated with the Extremely Bright GRB 130427A [ the science theme motivating the Athena+ mission, (2013) Two Types of Progenitors supernovae do not? [ [ (2014) 37 [ (1998) 17 [ Recombination Lines in H II Regions and their Implications [ 779 bright gamma-ray burst 130427A 130427A challenges the standard forward shock model Progenitors Single Component Synchrotron Afterglow Origin for the Late Optical to Multi-GeV Emission, Constant Density Medium [ MNRAS (1977) 377. [3] R. Chevalier & Z.-Y. Li, [4] M. De Pasquale, M. Page, D. A. Kann, et al., [7] C. Kouveliotou, J. Granot, J. Racusin, et al., [6] L. Hunt & H. Hirashita, [5] C. Fryer, G. Rockefeller, & P. Young, [9] T. Laskar, E. Berger, B. Zauderer, et al., [8] P. Kumar & B. Zhang, [11] A. Maselli, A. Melandri, L. Nava, et al., [12] K. Nandra, D. Barret, X. Barcons, et al., GRB 130427A afterglow: a test for GRB models [10] A. Levan, N. Tanvir, A. Fruchter, et al., [16] P. Sharma, A. Roy, B. Nath, et al., [13] A. Peimbert & M. Peimbert, [14] D. Perley, S. Cenko, A. Corsi, et al., [15] R. Sari, T. Piran & R. Narayan, [17] A. van der Horst, Z., Paragi, A. G. de Bruyn, et al., [18] N. Yadav, M. Dipanjan, P. Sharma, et al., [19] T. Weaver, R. McCray, J. Castor, et al., [20] W. Zheng & A. MacFadyen, PoS(MULTIF2017)071 Massimiliano De Pasquale -160500177). arXiv 8 Thank you for your comment. I want to remind that the GRBs by precessing thin jet have a foreseen flux or somehow lower power law. The rare persistence is due to the uncommon 1 − ) s 4 t 10 × 3 ( ∝ on-axis beaming, and itsSGRs late (Fargion decay 1999, several AA, 138, years 507; or Fargion century & Oliva, later may interface GRBs with late GRB 130427A afterglow: a test for GRB models DISCUSSION DANIELE FARGION: decay MASSIMILIANO DE PASQUALE: