**Exhibit 10(c) xxiii**

American Science &Engineering, Inc.

Change in Control &Severance Benefit Agreement

Thisis a SEVERANCE BENEFIT & CHANGE IN CONTROL Agreement (the “Agreement”)entered into between American Science & Engineering, Inc. (the “Company”,which term shall include any successor by merger, consolidation, sale ofsubstantially all of the Company’s assets or otherwise) and ___________ (“Executive”)effective as of the ___ day of _________________ (the “Effective Date”).

# 1.           Purpose of this Agreement.The Company hereby agrees to provide severance and change in control benefitsto Executive on the terms and conditions set forth in this Agreement. Thesebenefits are in lieu of any benefits that would otherwise be payable toExecutive under the severance pay plan, if any, maintained by the Company forthe benefit of senior executives or other Company employees, or by statute. Thisseverance agreement does not represent an employment contract for any definiteterm or period, which means that either Executive or the Company can terminateExecutive’s employment at any time, for any reason or no reason, and with orwithout notice.

# 2.           Term of Agreement. TheAgreement shall become effective on the Effective Date and shall terminate on March 31,2008; provided that this Agreement shall automatically be extended forsuccessive one year terms unless the Board provides Executive with writtennotice to the contrary at least thirty (30) days before the date the Agreementwould otherwise be so extended. Such notice, in the sole discretion of theBoard, may provide that the term will not be extended in the future, and/orthat there shall be no further automatic extensions of the Term.

# 3.           Definitions.The following terms as used in this Agreement shall have the followingmeanings:

## (a)           “Affected Award”means each Stock-Based Award held by Executive immediately prior to a Change inControl Qualifying Termination.

## (b)           “Affiliate” meansany business entity in which the Company holds, directly or indirectly, anequity, profits, or voting interest of 30% or more, and includes anysubsidiary.

## (c)           “Base Salary” means (i) thehighest annual rate of base salary payable to Executive by the Company duringthe one-year period ending on Executive’s Date of Termination or (ii) thehighest annual rate of base salary payable to Executive by the Company duringthe one-year period ending on the Change of Control, whichever is higher.

## (d)           “Board” means theBoard of Directors of the Company.

## (e)           “Cause” means, forpurposes of this Agreement, as determined by the Board in its reasonablejudgment: (i) Executive’s failure to perform (other than by reason

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of disability), ormaterial negligence in the performance of, his duties and responsibilities tothe Company or any of its Affiliates; (ii) material breach by Executive ofany provision of this Agreement or any other agreement with the Company or anyof its Affiliates; (iii) other conduct by Executive that could be harmfulto the business, interests or reputation of the Company or any of its Affiliates;(iv) fraud, embezzlement or other material dishonesty by Executive withrespect to the Company or any of its Affiliates, or (v) Executive’sconviction of, or pleading no contest to, any felony or other crime involvingmoral turpitude, or (vi) a breach of anyconfidentiality/non-competition/non-solicitation agreement. With respect to abreach of (i), (ii), (iii) or (vi), Executive shall be given thirty (30)days, after written notice of such breach, to cure a breach to the reasonablesatisfaction of the Company.

## (f)            “Change in Control”means the occurrence hereafter of any of the following:

## (i)            any Person,other than the Company or an Affiliate, becomes a beneficial owner (within themeaning of Rule 13d-3, as amended, as promulgated under the ExchangeAct), directly or indirectly, in one or a series of transactions, of securitiesrepresenting more than fifty percent (50%) of the combined voting power of theCompany’s then outstanding securities;

## (ii)           thestockholders of the Company approve a merger or consolidation of the Companywith any other Person, other than a merger or consolidation which would resultin the voting securities of the Company outstanding immediately prior theretocontinuing to represent (either by remaining outstanding or by being convertedinto voting securities of the surviving entity) more than fifty percent (50%)of the combined voting power of the voting securities of the Company or suchsurviving entity outstanding immediately after such merger or consolidation;

## (iii)          there occurs aclosing of a sale or other disposition by the Company of all or substantiallyall of the assets of the Company;

## (iv)          IncumbentDirectors cease for any reason to constitute at least a majority of the Board; *provided*, that any individual who becomesa member of the Board subsequent to the date hereof, whose election ornomination for election was approved by a vote of at least two-thirds of theIncumbent Directors shall be treated as an Incumbent Director unless he or sheassumed office as a result of an actual or threatened election contest withrespect to the election or removal of directors; or

## (v)           a completeliquidation or dissolution of the Company

## *provided*, that if any payment or benefitpayable hereunder upon or following a Change in Control (as defined herein)would be required to comply with the limitations of Section 409A(a)(2)(A)(v) ofthe Code and the guidance thereunder

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## in order toavoid an additional tax under Section 409A of the Code, such payment orbenefit shall be made only if such Change in Control constitutes a change inownership or control of the Company, or a change in ownership of the Company’sassets, described in IRS Notice 2005-1 or any successor guidance.

## (g)           “Change in ControlQualifying Termination” means a termination of employment if, during the periodof twelve (12) months following a Change in Control either the employment ofExecutive is terminated by the Employer****forany reason other than for Cause, or Executive terminates his or her employmentwith the Employer for “Good Reason” (as defined in Section 3(l) below).

## (h)           “Client” means anyPerson who is, or within the preceding eighteen (18) months was, a client,customer or portfolio company of the Company or any of its Affiliates.

## (i)            “Code” means theInternal Revenue Code.

## (j)            “Company” meansAmerican Science & Engineering, Inc.

## (k)           “Date of Termination”means the date on which Executive’s employment terminates.

## (l)            “Good Reason” means(i) any action by the Company which results in a material adverse changein Executive’s position, title, reporting relationship, authority, duties orresponsibilities as in effect immediately prior to the Change in Control; *provided, however,* that a sale or transferof less than all or substantially all of the business of the Company or any ofits subsidiaries or other reduction of less than all or substantially all ofits business or that of its subsidiaries, or the fact that the Company hasbecome a subsidiary of another company or that the securities of the Companyare no longer publicly traded, shall not be taken into account when determiningwhether a material adverse change in Executive’s authority, duties orresponsibilities has occurred; (ii) any reduction in Executive’s rate ofannual base salary for any fiscal year to less than the greater of 100% of therate of annual base salary payable to him or her in the completed fiscal yearimmediately preceding the Change in Control or 100% of the rate at which annualbase salary was payable to Executive immediately prior to such reduction, (iii) anyadverse change in Executive’s annual bonus opportunity, taking into accountboth the maximum earnable bonus and the targets on which the bonus is based, (iv) thefailure to provide Executive participation in an incentive plan tied to thelong-term growth in the value of the Company, which plan, whether equity- orcash-based, provided Executive with a comparable financial opportunity to thatprovided to Executive under the Company’s equity-based plan immediately priorto the Change in Control, but excluding an isolated, insubstantial andinadvertent reduction of annual base salary or annual bonus opportunity whichis not taken in bad faith and which is remedied by the Employer within five (5) businessdays after receipt of notice thereof given by Executive; (v) any failureof the Company to continue or cause to be continued in effect any retirement,life, medical, dental, disability, accidental death or travel insurance plan in

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which Executive wasparticipating immediately prior to the Change in Control unless the Companyprovides Executive with a plan or plans that provide at least substantiallyequivalent benefits (as to extent of coverage and as to employee cost), or thetaking of any action by the Employer that would adversely effect Executive’sparticipation in or materially reduce Executive’s benefits under any such planor deprive Executive of any material fringe benefit or perquisite enjoyed byExecutive immediately prior to the Change in Control, other than an isolated,insubstantial and inadvertent failure not in bad faith and which is remedied bythe Employer within five (5) business days after receipt of notice thereofgiven by Executive; or (vi) the Company requires Executive to be based atany office or location that is more than twenty-five (25) miles distant fromExecutive’s base office or work location immediately prior to the Change inControl, except if such new location is closer to Executive’s residence at thetime such requirement is imposed

## (m)          “Incumbent Directors”mean individuals who, as of the date of this Agreement, constituted the Board.

## (n)           “Non-CompetitionPeriod” means the period while Executive is employed by the Company and for oneyear after Executive’s employment terminates, except in cases of Change in Control QualifyingTerminations”.

## (o)           “Outstanding CompanyCommon Stock” means the outstanding shares of common stock of the Company.

## (p)           “Outstanding CompanyVoting Securities” means the outstanding voting securities of the Companyentitled to vote generally in the election of directors.

## (q)           “Person” means anyindividual, entity or other person, including a group within the meaning ofSections 13(d) or 14(d)(2) of the Securities Exchange Act of1934.

## (r)             “QualifyingTermination” means either (a) a termination of Executive’s employment bythe Employer****for any reason otherthan for Cause, (b) the Executive terminates his or her employment withthe Employer for “Good Reason” (as defined in Section 3(l) above), or(c) the Executive dies.

## (s)            “Short TermIncentive” means payments made pursuant to****theCompany’s short-term incentive plan.

## (t)            “Stock-Based Award”means any option, stock appreciation right, restricted stock or restrictedstock unit granted by the Company to Executive pursuant to the Company’s 2005Equity & Incentive Plan or any successor plan or agreement, or anyother equity compensation plan or agreement previously adopted by the Board ofDirectors of the Company in which Executive participated.

# 4.           Changein Control Severance Benefits

## (a)           Executive agrees thatonce any Person other than the Company, a direct or indirect subsidiary of theCompany, or an employee benefit plan of the Company or any 

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such subsidiary begins atender or exchange offer or a solicitation of proxies from the Company’ssecurity holders or takes other actions to effect a “Change in Control,” ashereinafter defined, Executive will not voluntarily terminate his or heremployment with the Company (or its Affiliates) until such Person has abandonedor terminated such efforts to effect a Change in Control or until a Change inControl has occurred. In the event that Executive voluntarily terminates his orher employment prior to the Change in Control, he/she will not be entitled toany payments or benefits under this Agreement or any severance pay plan, ifany, of the Company.

## (b)           In the case of aChange in Control Qualifying Termination, then Executive shall receive thefollowing payments and benefits, subject to the limitation set forth in Section 6:

#### (i)  *Accrued Salary.*The Company shallpay to Executive in a single cash lump sum, within ten (10) days followingthe date of termination, the sum of (1) all salary and commissions earnedby Executive as of the date of termination but not yet paid and (2) Executive’saccrued bonuses and accrued vacation earned through the date of termination.****In addition, the Company shall pay toExecutive in cash within five (5) business days of the date oftermination, reimbursement for any unpaid, valid business expenses that areapprovable in accordance with Company policy.

#### (ii)  *Severance Pay.*TheCompany shall pay to Executive in a single lump sum, within sixty (60) calendardays of the date of termination, an amount equal to one times the average ofthe last five years of each of Base Salary and target Short Term Incentivepayments. In the event a Change of Control occurs prior to the date on whichExecutive has worked for the Company and/or its Affiliates for five years ofservice, the amount paid will be based on the average of the aggregate BaseSalary and Short Term Incentive payments for the years actually worked.

#### (iii)  *COBRA Premiums.*TheCompany shall pay 100% of the premium toward COBRA coverage for Executive,Executive’s spouse and his qualifying dependents, for a period of eighteen (18)months following the Date of Termination. Notwithstanding the foregoingprovisions of this subsection, if Executive becomes employed by anotheremployer and is eligible for medical, dental or life insurance coverage that issubstantially equivalent (as to extent of coverage and as to employee cost) tothe coverage of the same type that he or she were entitled to receive underthis subsection, the Employer’s obligation to Executive and his or herdependents under this subsection shall cease with respect to that type of coverage.In addition, in the event that the Company is unable to provide COBRA toExecutive as provided herein, Company will pay to Executive an equivalentamount in reimbursement for medical insurance (of equivalent benefits and cost)premiums paid by Executive.

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#### (iv)  *Stock-Based*Awards.

##### (1)        Tothe extent not already vested and exercisable, each Affected Award shall becomefully vested and exercisable upon the occurrence of the Change in ControlQualifying Termination. In the event Executive holds an Affected Awardrequiring exercise, the Company shall give Executive adequate notice andopportunity to exercise the Affected Award. Notwithstanding the foregoing, tothe extent permitted by the equity plan under with the Stock-Based Award wasgranted, nothing in this Agreement shall preclude the Company from acceleratingthe vesting and exercisability of an Affected Award to an earlier period, andterminating unexercised awards as provided under the equity plan.

##### (2)        Notwithstandingthe provisions of this Section 4 to the contrary, if a Stock-Based Awardheld by Executive is not assumed or replaced, or to be assumed or replaced,upon a Change in Control, each Stock-Based Award held by such Executive,whether or not he or she has experienced a Qualifying Termination, shall becomefully vested and exercisable, effective immediately prior to the Change inControl.

##### (v) *Additional Discretionary Payments.*TheCompany may make an additional cash or stock settlement at the sole discretionof the Board.

# 5.           Severance Benefits.  In the case of a Qualifying Termination thatis not a Change in Control Qualifying Termination, then Executive shall receivethe following payments and benefits, subject to the limitation set forth in Section 6:

## (a)           *Accrued Salary.*The Company shall pay toExecutive in a single cash lump sum, within ten (10) days following thedate of termination, the sum of (i) all salary and commissions earned byExecutive as of the date of termination but not yet paid and (ii) Executive’saccrued bonuses and accrued vacation earned through the date of termination. ** **Inaddition, the Company shall pay to Executive in cash within five (5) businessdays of the date of termination, reimbursement for any unpaid, valid businessexpenses that are approvable in accordance with Company policy.

## (b)           *Severance Pay.*The Company shall pay toExecutive in a single lump sum, within sixty (60) calendar days of the date oftermination, an amount equal to one times the average of each of the last threeyears of Base Salary. In the event a Qualifying Termination occurs prior to thedate on which Executive has worked for the Company and/or its Affiliates forthree years of service, the amount paid will be aggregate of the average BaseSalary for the years actually worked.

(c)*           COBRA Premiums.*TheCompany shall pay 100% of the premium toward COBRA coverage for Executive,Executive’s spouse and his qualifying dependents, for a 

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period of one (1) yearfollowing the date of employment termination. Notwithstanding the foregoingprovisions of this subsection, if Executive becomes employed by anotheremployer and is eligible for medical, dental or life insurance coverage that issubstantially equivalent (as to extent of coverage and as to employee cost) tothe coverage of the same type that he or she were entitled to receive underthis subsection, the Employer’s obligation to Executive and his or herdependents under this subsection shall cease with respect to that type ofcoverage.

# 6.           Limitation on Payments.If any payments pursuant to the Agreement would be subject to tax under Section 4999of the Internal Revenue Code (the “Payments”), then Executive shall receiveeither (i) the full Payments or (ii) such lesser amount of thePayment which would result in no portion of such Payments being subject to the Section 4999tax, whichever yields the greatest net amount to Executive on an after-taxbasis (applying the then highest aggregate marginal tax rates). If a reductionof the Payments is required pursuant to subpart (ii), then Executive will be permittedto request which component items of the Payment will be reduced provided,however, that Executive must provide to the Company in writing his/her requestwithin the reasonable time period established by the Company and the Companymust in its discretion consent to such request (or else the Company shall makeits own determinations with respect to which Payment items are to be reduced). TheCompany may elect to contest at its expense any initial IRS determination withrespect to an Executive. Executive shall cooperate reasonably with the Companyin any effort by the Company to contest an IRS determination under thisparagraph, including by the making of such filings and appeals as the Companymay reasonably require, but nothing herein shall be construed as requiringExecutive to bear any cost or expense of such a contest or in connectiontherewith to compromise any tax item (including without limitation anydeduction or credit) other than the Section 4999 tax and related interestand penalties, if any, that are the subject of the contested IRS determination.In the event of any underpayment or overpayment under this Agreement, asdetermined by the nationally recognized accounting firm, the amount of suchunderpayment or overpayment shall be promptly paid to Executive or refunded tothe Company, as the case may be, with interest at 120% of the applicableFederal rate provided for in Section 7872(f)(2) of the InternalRevenue Code.

## All taxdeterminations under this Section 6 shall be made at the Company’s expenseby a nationally recognized accounting firm selected by the Company in itsreasonable discretion. Any good faith determinations of this accounting firmmade hereunder shall be final, binding and conclusive upon the Company andExecutive.

# 7.           Noncompetition. Duringthe Non-Competition Period, Executive shall not, directly or indirectly,whether as owner, partner, investor(nothing contained in this Agreement, however, shall prevent Executive frompassive ownership of two percent (2%) or less of the voting stock of anypublicly traded company (other than the Company)), consultant, agent,employee, co-venturer or otherwise, compete with the Company or any of itsAffiliates within the United States or in any country in which the Company orany of its Affiliates is then doing business. Specifically, but withoutlimiting the foregoing, Executive agrees not to engage in any manner in anyactivity that is directly or indirectly competitive or potentially competitivewith the business of the Company or any of its Affiliates as conducted or underconsideration at any

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time during Executive’s employment. Executive furtheragrees that while Executive****is employed bythe Company and during the Non-Competition Period, Executive will not hire orattempt to hire any employee of the Company or any of its Affiliates, assist insuch hiring by any Person, encourage any such employee to terminate his or herrelationship with the Company or any of its Affiliates, or solicit or encourageany customer or vendor of the Company or any of its Affiliates to terminate ordiminish its relationship with them, or, in the case of a customer, to conductwith any Person any business or activity which such customer conducts or couldconduct with the Company or any of its Affiliates.

# 8.           PaymentObligations Absolute. Upon a Change in Control Qualifying Termination or aQualifying Termination, the Company’s obligations to pay the benefits describedin Section 4 (or the benefits described in Section 5 for a QualifyingTermination) shall be absolute and unconditional and shall not be affected byany circumstances, including, without limitation, any set-off, counterclaim,recoupment, defense or other right which the Company or any Affiliate may haveagainst any Executive; provided, however, that the Company may delay thepayment of any amounts due hereunder for six months following termination ofExecutive’s employment with the Company if necessary to comply with the “specifiedemployee” rules pursuant to Section 409A of the Code. In no eventshall Executive be obligated to seek other employment or take any other actionby way of mitigation of the amounts payable to Executive under any of theprovisions of the Agreement and, except as otherwise provided in Section 7,in no event shall the amount of any payment hereunder be reduced by anycompensation earned by Executive as a result of employment by another employer.

# 9.           Amendment.This Agreement may be amended or modified only by a written instrument signedby Executive and by a expressly authorized representative of the Company.

# 10.         Withholding.All payments and benefits hereunder shall be subject to reduction forapplicable tax withholdings.

# 11.         Indemnification.The Company agrees to pay all costs and expenses (including without limitationfees and expenses of counsel) incurred by any Executive in connection withefforts to enforce his or her rights under this Agreement and will indemnifyand hold harmless any Executive from and against any damages, liabilities andexpenses (including without limitation fees and expenses of counsel) incurredby Executive in connection with any litigation or threatened litigation,including any regulatory proceedings, arising out of the making, performance orenforcement of this Agreement.

# 12.         Source of Payment. Nothingherein shall be construed as establishing a trust or as requiring the Companyto set aside funds to meet its obligations hereunder. Notwithstanding theforegoing, if the Board in its discretion so determines, the Company mayestablish a so-called “rabbi trust” or similar arrangement to assist it inmeeting any such obligations that it may have.

13.           Required Release andNon-Disparagement. The Company’s obligation to provide severance pay andother benefits under this Agreement, however, is subject (a) to Executive’s

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signing in a timely manner a release of claims infavor of the Company in the form to be provided by the Company (the “Release”)and of Executive not revoking the Release in a timely manner thereafter; and (b) toExecutive’s meeting in full his or her obligations under any other agreementsin effect between you and the Company. You agree to not make any oral orwritten communication to any person or entity which has the effect of damagingthe reputation of, or otherwise working in any way to the detriment of,AS&E, its officers, directors or management. You also acknowledge yourcontinuing responsibility to honor the non-compete and non-solicitationobligations previously undertaken by you for a period of one year from theTermination Date.

# 14.           Notices. Any and all notices,requests, demands and other communications provided for by this Agreement shallbe in writing and shall be effective when delivered in person or deposited inthe United States mail, postage prepaid, registered or certified, and addressedto Executive at his last known address on the books of the Company or, in thecase of the Company, at its principal place of business, attention of thePresident, or to such other address as either party may specify by notice tothe other actually received.

# 15.         Entire Agreement. ThisAgreement constitutes the entire agreement between the parties and supersedesall prior communications, agreements and understandings, written or oral, withrespect to the terms and conditions of Executive’s severance from employmentwith the Company and its Affiliates.

# 16.         Severability. Eachprovision of this Agreement shall be considered severable such that if any oneprovision or clause conflicts with existing or future applicable law, or maynot be given full effect because of such law, this shall not affect any otherprovision of the Agreement which, consistent with such law, shall remain infull force and effect. All surviving clauses shall be construed so as toeffectuate the purpose and intent of the parties.

# 17.         Headings. The headingsand captions in this Agreement are for convenience only and in no way define ordescribe the scope or content of any provision of this Agreement.

# 18.         Counterparts. ThisAgreement may be executed in two or more counterparts, each of which shall bean original and all of which together shall constitute one and the sameinstrument.

# 19.         Governing Law. ThisAgreement shall be governed by the laws of the Commonwealth of Massachusettswithout regard to its conflicts of laws principles.

|              |   |                                          |   |
|-------------------|--------|-----------------------------------------------|--------|
| [Named Executive] |   | AMERICAN SCIENCE & ENGINEERING, INC. |   |
|              |   |                                          |   |
|              |   | By:                                           |   |   |
|              |   |                                          |   |   |
|              |   | Name:                                         |   |   |
|              |   |                                          |   |   |
|              |   | Title:                                        |   |   |

 

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