In our analysis of the SDSS spectrum, taken very close in time to the photometric peak of the light curve see Fig. This baseline constant spectrum is shown as a dashed red line in the middle panels of Fig. The middle panel shows the observed, calibrated SDSS spectrum, together with the best-fitting host galaxy model continuum plus narrow emission lines red dashed line.
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The bottom panel shows the difference spectrum — , where the rapidly time-varying emission components emerge. The middle panel shows the observed, calibrated SDSS spectrum, together with the best-fitting model host galaxy continuum plus narrow emission lines red dashed line. The bottom panel finally shows the difference spectrum — , where the rapidly time-varying emission components emerge.
All these estimates come with both statistical and systematic uncertainties of about 0.
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Given the implied size of the BLR, and the observed X-ray spectra both XMM—Newton and Chandra can be fitted with unabsorbed power laws , they conclude that an obscuration event, in the form of a large-scale cloud passing in front of the central source and of the BLR, is not consistent with the time-scale of the observed fast flare, nor with the spectral slope of the Chandra spectrum. It appears, then, that the intrinsic emission of the AGN is fading rapidly, possibly due to a decrease of the accretion rate on to the central BH.
Larger discs, needed if the observed optical light is produced from viscous dissipation within the disc itself, would evolve on even longer time-scales. It appears, then, that a physical process is required that can give rise to rapid enhancement of the accretion rate, a process that delivers large quantities of matter very close to the central BH, where viscous or thermal times are the shortest. In the following, we describe why we believe that a TDE is a much more natural interpretation for this peculiar transient event. We first analyse in more detail the evolution of the flare, as traced by the Stripe light curve.
This leaves us with 50 high-quality epochs of photometry. The top panel of Fig. Panel a : the time evolution of the nuclear luminosity is shown with the coloured circles where each colour identifies one epoch of the SDSS Stripe observations. In all panels, the black solid line connecting the points is drawn to guide the eye. As a reference, the plot shows also the constant baseline host galaxy SED in the five optical bands black empty stars, as in Fig. As a simple phenomenological test of the above scenario, we have also fitted the same spectral evolution data shown in Fig.
Panel c of Fig. We discuss in the following section the constraints on the TDE model parameters we can obtain by modelling these data. For each of the first 16 epochs of the cleaned Stripe light curve, spanning the first five rest-frame years, shown in Fig. The colour code is identical to that of Fig. As in Fig. The left-hand panel of Fig. Just as a reference point for discussion, we mark with a black star in Fig. The black dashed lines show the contours of equal peak time, in rest-frame years.
Right: the relation between the critical black hole mass M BH, crit x -axis , above which stars are swallowed whole and no tidal disruption flare can be observed and the star's mass y -axis is shown as a black solid line for the case of non-spinning black holes leftmost line and maximally spinning black holes rightmost line. The right-hand panel of Fig. To conclude this section, we note that a prominent re-brightening flare was observed about four rest-frame years after the peak.
This subflare is characterized by a relatively constant continuum slope and photospheric temperature, and has a fluence of about 5. It is just due to a fortuitous coincidence that the first SDSS spectrum, showing the prominent broad emission lines that led to type-1 AGN classification, was taken very close in time to the flare peak, and we suspect this crucial detail had been overlooked. The analysis presented in the previous section, however, suggests that the observed light-curve evolution, and, in particular, the overall energetics of the event are consistent with the amount of accreted mass being a substantial fraction of a massive main-sequence star.
The X-ray spectrum observed by XMM—Newton close to the peak of the light curve is consistent with a power law of index 2. In general, too little is currently known about the spectral formation mechanisms in TDE, across the entire electromagnetic spectrum, to be able to reject the TDE interpretation on the basis of the X-ray spectral shape only.
Moreover, we note that, in general, optically selected TDE tend to have low photospheric temperatures and be X-ray faint, while X-ray-selected TDE tended to be hot when thermal and optically faint see e. There are, moreover, other pieces of evidence that are not straightforward to interpret within the simplest TDE scenario we have described so far. In particular, the properties of the emission lines observed in the spectra are not easily explained by a TDE model, as we discuss in the following subsections.
In fact, two possible alternative sites of broad emission-line production have been invoked for TDE. According to this scenario, high-ionization lines should appear first, followed by lower ionization lines later on during the outburst. They, however, predicted both emission and absorption lines, and significant bulk blueshift of the lines, contrary to what is typically observed. For the particle densities inferred for the BLR emitter, recombination is very fast, so the lines respond effectively instantaneously to flux variations from the central source.
Thus, the rapid luminous flare we observed between and , must have illuminated a pre-existing structure, whose spatial distribution and kinematics closely resemble those of BLR of actively growing SMBH. The likelihood of the observed configuration, with the broad emission lines appearing transiently in response to a rapid nuclear TDE, depends on the lifetime of the BLR structure in objects where the central black has ceased accreting at substantial rates.
This must depend, in turn, on the dynamical status of the BLR itself is it outflowing, inflowing, circulating? A detailed analysis of these issues is beyond the scope of this paper. The narrow emission-line diagnostics see Fig. As we discussed in the introduction, there is substantial uncertainty in the true rate of tidal stellar disruption in galactic nuclei, with current observationally determined rates lying factors of a few to 10 below the theoretical expectations.
Here, for illustration purposes, we adopt a generic i.
The grey band represents a 1 order-of-magnitude uncertainty in the TDE rates. In each plot the thin blue solid line shows the ratio of the black to red solid lines, i. In the case of gaseous accretion, most attempts to reproduce the AGN luminosity function have implied peak luminosities of the order of the Eddington luminosity. In fact, it is unlikely that a single mechanism could provide a complete description of gaseous AGN triggering. The exact behaviour of the TDE fraction at such high luminosities, however, critically depends on the SMBH spin distribution, as rapidly spinning BHs can tidally disrupt stars even if they are very massive see the right-hand panel of Fig.
As a term of reference, we also show in Fig. Further clues on the nature of elusive AGN, and on the true fraction of TDEs among them could come from a detailed study of the IR emission from those sources, which could reveal either the presence of a deeply obscured AGN or the transient echo of the TDE emission. We have used late-time photometric and spectroscopic observations of the source to build a host galaxy model, that we used to carefully analyse the nuclear host-subtracted light curve of the flare in all five SDSS bands.
Perhaps due to the serendipitous nature of its discovery, it is also one of the few cases in which both optical and X-ray emission contribute substantially to the bolometric luminosity of the event, suggesting that accretion on to BHs from tidally disrupted stellar debris can also give rise to powerful Comptonizing coronae.
In most previous cases, optically selected TDE had low photospheric temperatures and were X-ray faint, while X-ray-selected TDE tended to be hot and optically faint see e. If the continuum evolution and the overall energetics of the event strongly suggest a TDE interpretation, the emission-line spectra tell a more complicated story. The BLR, which responded almost instantaneously to the strong illumination from the central flaring source in , is too extended about 30 light days and massive more than hundred solar masses to have been created by the debris of a disrupted star, and must have been left, in the dark, from previous episodes of more prolonged accretion on to the central BH.
Also, the narrow emission lines, which we see unchanged between and , possibly indicate that the central BH was active as little as 10 4 yr ago, although it is not straightforward to estimate exactly at which level, as the narrow emission lines could be also partly excited by the powerful star formation observed in this galaxy.
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Such a complex interplay must not be too exceptional, also given the fact that this TDE was discovered in a relatively small parent sample. We are, indeed, used to think of AGN as being either type-1 un-obscured or type-2 obscured , based on the properties of their optical emission lines. This is particularly important for TDEs, of course, which have flare durations of a few years, at most, but could be relevant for other forms of BH fuelling, too.
A few lessons can be learned from this work: probably the most compelling is that an accurate observational determination of TDE rates requires searches that do not a priori exclude objects previously classified as AGN, and needs to fully account for the exact time when such classification was first made.
Also, we showed that TDE confirmation is far from straightforward, and requires well-sampled optical light curves, and would be aided by repeated, early spectroscopic observations, too. In addition, deep and wide X-ray observation with the right cadence have the advantage that the TDE-produced light becomes confused with the host galaxy stellar background at much later stages at these energies, thus allowing flares to be identified with less well-sampled light curves and on longer time-scales.
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Insurance information is not needed. Measure your blood pressure, weight, blood sugar levels, and pulse. Call for times and more information. Selma Vereget, selma. For women forty and older, please call to set up your free fitness consultation. Christine will sit down with you and listen to what you would like to do to feel and look better. Please don't let knee or back issues keep you from activity you enjoy as a part of your life.
Please call Christine at It will only take 30 minutes. Located in Fenton. Christine Bond, cbondfit gmail. Wednesdays — a. Mondays — a. Leigh Anne Hoormann, leighanne. Cordell Planning Chesterfield Office. October 1 — p. October 3 — p. Cordell Planning Partners, an elder care law firm dedicated to providing smart solutions for seniors, is hosting a complimentary workshop in Chesterfield to highlight the legal complexities facing seniors as they age.
The workshop will take place from October 1 from p. Registration for the free workshop is available online at eldercarelaw. Planning and protecting estates and valuable belongings can be a complicated process. It is critical to understand all the available options and identify if a current plan meets any goals seniors may have. Cordell Planning Partners workshop topics include:. Register for a free Cordell Planning Partners workshop to learn more about the steps seniors need to take to ensure that their assets and future are protected. The workshop will take place in the first-floor meeting room.
Light snacks will be provided, and parking is free for this event. Please visit www. MU Extensions in St. October 5 — a. You'll learn how to save precious time by meal prepping with fresh produce, have the best lawn, and more. Check in is at a. Matt Lebon will begin by discussing Edible Landscaping at a. Lunch is provided from a. You will choose your session topics when you register. October 8 — p. Understanding Financial Statements: Where is Your money going?
October 8, p. Manage Your financials - Don't let Them Manage You is designed for business owners, managers, accountants, bankers and consultants who need to know how to turn financial statements into useful management tools. During this course, you will learn to identify key business information that is captured on the income statement and balance sheet. You will learn to calculate several ratios and understand what those ratios mean in terms of business productivity and success. You will leave this session with a greater understanding of how to read and interpret financial documents and how to use that information to drive business decisions.
Florissant Avenue, Ferguson, MO Lynette Oliver, beckld missouri. Autumn View Gardens — October 10 — p. Park Place Senior Living - October 12 — a. Free seminar with important information for senior citizens and the adult children who love them. You have saved for your retirement and you fear a costly health crisis What should you do?
This seminar is also being offered on Saturday, October 12, at a. RSVP for this event at the same toll-free number. Diane Distl, ddistl beckelderlaw. October 14 — p. Metered handicap parking is available on Scott Avenue or two-hour handicap parking is available at the Taylor Avenue Building, S. Taylor Avenue. Open to all; no RSVP necessary. Pizza and beverages will be available. Jeff Brandt, jeffrey. Ellisville Parks and Recreation. October 15, 22, 29 — p. October 17, 24 — — p. November 5, 12, 19 — to p. November 7 and 14 — to p. November 18, 25 — to p.
December 2, 9 — to p. Learn to dance or improve your moves in Bluebird Park this Fall! Instructor: Karen Merlin. Line Dance for Adults: Monday evenings Nov. Description: You can learn basic line dancing steps at an easy going pace. Be prepares for lots of fun, cardiovascular exercise and the opportunity to make new friends. No prior experience necessary or partner required. Easy Social Dance: Tuesday evenings Oct. You will learn to dance to any music, fast or slow.
Simple basics of various rhythms will be taught as well as free-style dancing. Partner or singles are welcome. Latin Dance for Beginners: Thursday evenings Oct. No experience is necessary. Partners or singles are welcome. Non-rubber soled shoes recommended. Register online: ellisville. Meghan Mollet, mmollet ellisville. October 22 — a. Are you ready to make the Government your next customer? October 22, a. Have you ever wondered what it takes to do business with the federal government? Join the SBA, Procurement Technical Assistance Center PTAC and the Small Business Development Center and learn how government contracting works, how specialized federal certifications can boost your business and also get acquainted with the assistance available to you to help you as you navigate through this process.
Louis County Library. November 2 — a. Starting and Managing a Small Business on November 2, a. Are you thinking about starting and managing a small business in Missouri? Designed for individuals who are considering starting a business, have made the decision to start or who have been in business for less than two years, this program will discuss the basics of business ownership, planning for success, organizational forms of business, legal and regulatory environment, record keeping and information management, marketing, financing and resources.
For more details on registration www. This is a free event at St. Louis County Library S. Lindbergh Blvd, St. Louis, MO Louis County Library, ,. Louis Community College. November 5 thru December 3 — p. An intensive, four-session, individually customized course designed to provide new and aspiring entrepreneurs with the tools and resources to create a solid business plan.
These sessions are enriched with guest speakers from various disciplines including the legal profession, marketing, human resources and financing. In addition, each participant will begin by taking the Growth Wheel assessment and receive customized tools based on this assessment to assist as you build your plan. Weekly homework assignments are given, and participation is required to be successful in the class.
Continued counseling from a business counselor and certified life coach is available after the completion of the class. Please bring a laptop or electronic device to class for working on your business plan. Louis Community College, ,. November 8 — a. Marla Berg-Weger and Dr. Examples of assessment and intervention strategies will be highlighted.
Interactive applications will provide participants with the opportunity to discuss, practice and reflect on strategies for assessing and intervening with older adults, particularly related to common geriatric syndromes. Louis, MO Free parking is available in front of the building You may pre-register online at www. Karen Bolinger, conted slu. December 6 — p.
Total Hours: The library's biggest business event of the year, packed with outstanding are agencies devoted to helping aspiring entrepreneurs, current business owners and nonprofits. You'll discover the help you need from our workshops and free legal assistance clinic, all while you build your network of fellow entrepreneurs. Louis County Library, S. Ballpark Village. Louis teammates, Kelly Chase and Darren Pang. Jhod Cardinal, jhod upstreamflix. The Missouri History Museum. October 2 — to a.
Back by popular demand. This All Girl Band performs music with a narrative about the all-girl bands of the s. Lynn Hamilton, lynn maturityanditsmuse. Chamber Project, St. Concert on October Be a part of a working rehearsal with Chamber Project St. Learn about the process of making music in this casual, interactive musical experience. Ask questions about the music, the instruments, the musicians - whatever comes to mind. A moderator will facilitate engagement between the audience and the musicians, who will be preparing a piece for the upcoming concert on October A truly unique opportunity to learn about the process of making music come alive.
Dana Hotel, info chamberprojectstl. Union Avenue Opera. October Louis, MO,. The evening will be hosted by Kathy Lawton Brown of Classic Tickets are on sale now. Call or visit unionavenueopera. Union Avenue Opera was founded in to bring affordable, professional, original-language opera to St. Louis, a mission the company continues to pursue to this day. UAO is committed to hiring the most talented artists, directors, designers and technicians both locally and from across the United States. UAO provides promising young singers the first steppingstone of their professional career.
UAO is a publicly supported c 3 nonprofit organization registered in Missouri. OPERA America is the national membership organization for artists, administrators and audiences, dedicated to support the creation, presentation and enjoyment of opera. Central West End. October 11 - p. Often, the lens we use to hear music changes with the passage of time.
Despite early popularity, Mendelssohn was met with anti-semitism and denigration of his work. Though he was not regarded as a success during his lifetime, his work is now treasured for its creative originality. Growing up in the American South, Florence Price fought hard for her success in a country divided by race and deeply ingrained gender roles.
This is their first performance in an exciting new space, projects plus gallery in the Central West End. October 12 — to p. Louis Banjo Club will provide an afternoon of lively music played on "America's fun instrument - the four-string banjo". Listen to a dozen banjo players playing the songs you know. Euclid in the CWE, St. For more information, call or visit our website: www. Great Cajun food and drinks from their menu. Did we mention the music is free? Don Dempsey, stlouisbanjoclub gmail.
Afton, St. Louis Parks and Recreation. October 12 — a. December 14 — a. Here is your opportunity to clean out the clutter for vendors or collect a rare treasure or bargain as a buyer. Free Admission a. Caitlin Reuter, creuter stlouisco. Fenton Parks and Recreation. October 18 — p. We are celebrating Thanksgiving, harvest time and cooler weather with a night filled with great food, dancing, and music.
This feel good music is guaranteed to put a smile on your face. Pre-registration is required by October Menu: Polish sausage, German potato salad, German red cabbage, rye bread and butter, German chocolate cake, ice-tea, coffee, apple cider Friday, October 18, - p. Rec Supervisor, parksandrec fentonmo. Washington University Friedman Center for Aging. October 22 — p. Bring friends, family and colleagues to hear speakers present in a quick, engaging and visual style. Registration is free, but required, food and drinks will be provided.
Natalie Galucia, ngalucia wustl. Now thru October 27 — p. Fidencio Fifield-Perez faces scrutiny and political debate every day in the United States. Born in Oaxaca, Mexico, his family migrated to North Carolina for a better life and more opportunities. This exhibition is presented in conjunction with Innovations in Textiles , a regional collaborative event celebrating fiber art.
Michael Powell, michael. The Missouri History Museum — E. Desmond Lee Auditorium. November 6 — a. Performance: to a. Admission is free with handicapped access. For additional information, contact Lynn Hamilton at lynn maturityanditsmuse. Afton Community Center. December 1 — p. Santa will light the holiday tree and pass out treats to children. Call for more information.
Who Killed Sears? Fifty Years on the Road to Ruin
Louis County Parks, ,. THE ST. December 11 — a. Louis Strutters on Wednesday, December The Strutters have been performing fast tapping precision dance routines with a rich history of skill and dedication thirty years. This high-kicking chorus line perform rhythm tap dances with style and glamour. Doors open at a. Information: Lynn Hamilton lynn maturityanditsmuse.
Two outrageously funny teams duel it out for points and your laughs. You choose the winners… the teams provide the funny. This show is suitable for everybody. We host shows every Saturday night and on the third Friday of every month at p. It's percent clean comedy and always a blast. Mike Mcguire, cszstlouis gmail.
Fridays — p. Fridays at Fairwinds River's Edge, please join us for happy hour with live entertainment Fridays at p. RSVP required: Stacy Welker, swelker leisurecare. Lighthouse for the Blind. National Preparedness Month every September encourages families, businesses, communities and schools to develop emergency survival plans. In St. Louis, Missouri, 48 legally blind employees at Lighthouse for the Blind — Saint Louis LHB are doing their part by producing medical kits; catheters, adhesives, pandemic flu kits, aerosol and liquid cleaners among many products for business, consumer and government customers.
Jeff Dunap, jmdpr2 gmam. Introducing a new U. Fun-Tastic Historical Fiction book for children. Then tickety-boo he travels to each of the U. States where he meets animal characters who share the history of their state, capital and Capitol Buildings, with tales filled with fun and facts that allow children of all ages to learn American history fun-tastically. Henry, Miguel, and I have included the Blog address so you can check it out, and sign up for his Weekly Blog Post, or order any of the books now available.